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A practical multi-lane factor model of bridges based on multi-truck presence considering lane load disparities

《结构与土木工程前沿（英文）》 2021年第15卷第4期页码 877-894 doi: 10.1007/s11709-021-0756-2

摘要： Many bridge design specifications consider multi-lane factors (MLFs) a critical component of the traffic load model. Measured multi-lane traffic data generally exhibit significant lane disparities in traffic loads over multiple lanes. However, these disparities are not considered in current specifications. To address this drawback, a multi-coefficient MLF model was developed based on an improved probabilistic statistical approach that considers the presence of multiple trucks. The proposed MLF model and approach were calibrated and demonstrated through an example site. The model sensitivity analysis demonstrated the significant influence of lane disparity of truck traffic volume and truck weight distribution on the MLF. Using the proposed approach, the experimental site study yielded MLFs comparable with those directly calculated using traffic load effects. The exclusion of overloaded trucks caused the proposed approach, existing design specifications, and conventional approach of ignoring lane load disparity to generate comparable MLFs, while the MLFs based on the proposed approach were the most comprehensive. The inclusion of overloaded trucks caused the conventional approach and design specifications to overestimate the MLFs significantly. Finally, the benefits of the research results to bridge practitioners were discussed.

关键词： bridges multi-lane factor traffic load lane load disparity multi-truck presence weigh-in-motion data

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Ozone kinetics of dimethyl sulfide in the presence of water vapor

Haitao WANG

《环境科学与工程前沿（英文）》 2013年第7卷第6期页码 833-835 doi: 10.1007/s11783-013-0570-8

摘要： The outdoor smog chamber was used to thorough investigate the rate constants of gas-phase reaction between dimethyl sulfide (DMS) and ozone (O ) under conditions of relative humidity 55.0%–67.8% at (296±2)K for the first time. The rate constants were measured, at a total pressure of 1 atm, to be (10.4±0.2) × 10 cm ·molecule ·s at relative humidity of 67.5%±0.3% at 298K, (10.1±0.1) × 10 cm ·molecule ·s at relative humidity of 66.5%±0.5% at 296K, (7.75±0.39) × 10 cm ·molecule ·s at relative humidity of 64.8%±0.1% at 294K and (3.42±0.21) × 10 cm ·molecule ·s at relative humidity of 55.8%±0.8% at 295K. Base on these results, it is possible to see the reaction of O /DMS in the presence of water vapor as an important sink for DMS in the earth atmosphere.

关键词： rate constants ozone (O₃) dimethyl sulfide (DMS) water vapor

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Surface water treatment benefits from the presence of algae: Influence of algae on the coagulation behavior

Yanxia Zhao, Huiqing Lian, Chang Tian, Haibo Li, Weiying Xu, Sherub Phuntsho, Kaimin Shih

《环境科学与工程前沿（英文）》 2021年第15卷第4期 doi: 10.1007/s11783-020-1350-x

摘要： Abstract • Emerging titanium coagulation was high-efficient for algae-laden water treatment. • Polytitanium coagulation was capable for both algae and organic matter removal. • Surface water purification was improved by around 30% due to algae inclusion. • Algae functioned as flocculant aid to assist polytitanium coagulation. • Algae could enhance charge neutralization capability of polytitanium coagulant. Titanium-based coagulation has proved to be effective for algae-laden micro-polluted water purification processes. However, the influence of algae inclusion in surface water treatment by titanium coagulation is barely reported. This study reports the influence of both Microcystis aeruginosa and Microcystis wesenbergii in surface water during polytitanium coagulation. Jar tests were performed to evaluate coagulation performance using both algae-free (controlled) and algae-laden water samples, and floc properties were studied using a laser diffraction particle size analyzer for online monitoring. Results show that polytitanium coagulation can be highly effective in algae separation, removing up to 98% from surface water. Additionally, the presence of algae enhanced organic matter removal by up to 30% compared to controlled water containing only organic matter. Polytitanium coagulation achieved significant removal of fluorescent organic materials and organic matter with a wide range of molecular weight distribution (693–4945 Da) even in the presence of algae species in surface water. The presence of algae cells and/or algal organic matter is likely to function as an additional coagulant or flocculation aid, assisting polytitanium coagulation through adsorption and bridging effects. Although the dominant coagulation mechanisms with polytitanium coagulant were influenced by the coagulant dosage and initial solution pH, algae species in surface water could enhance the charge neutralization capability of the polytitanium coagulant. Algae-rich flocs were also more prone to breakage with strength factors approximately 10% lower than those of algae-free flocs. Loose structure of the flocs will require careful handling of the flocs during coagulation-sedimentation-filtration processes.

关键词： Coagulation Polytitanium chloride Coagulation behaviour Algae Floc property

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Accelerated degradation of orange G over a widepH range in the presence of FeVO

Xiaoxia Ou, Jianfang Yan, Fengjie Zhang, Chunhua Zhang

《环境科学与工程前沿（英文）》 2018年第12卷第1期 doi: 10.1007/s11783-018-1013-3

摘要： In this study, FeVO was prepared andused as Fenton-like catalyst to degrade orange G (OG) dye. The removalof OG in an aqueous solution containing 0.5 g·L FeVO and 15 mmol·L hydrogen peroxide at pH 7.0 reached 93.2%. Similar rates were achievedat pH 5.7 ( = 0.0471 min ), pH 7.0 ( = 0.0438 min ), and pH 7.7 ( = 0.0434 min ). The FeVO catalyst successfullyovercomes the problem faced in the heterogeneous Fenton process, i.e.,the narrow working pH range. The data for the removal of OG in FeVO systems containing H O conform to the Langmuir–Hinshelwood model ( = 0.9988),indicating that adsorption and surface reaction are the two basicmechanisms for OG removal in the FeVO –H O system. Furthermore, the irradiationof FeVO by visible light significantly increasesthe degradation rate of OG, which is attributed to the enhanced ratesof the iron cycles and vanadium cycles.

关键词： Azo dye Degradation FeVO₄ Kinetics Advanced oxidation processes

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Impact of solids on biphasic biodegradation of phenanthrene in the presence of hydroxypropyl- β

Zhenyi ZHANG, Chihiro INOUE, Guanghe LI,

《环境科学与工程前沿（英文）》 2010年第4卷第3期页码 329-333 doi: 10.1007/s11783-010-0232-z

摘要： The consequence of polycyclic aromatic hydrocarbons (PAHs) in the environment is of great concern. The hydrophobic properties of PAHs significantly impact phase distribution causing limited bioavailability. Enhanced biodegradation has been extensively carried out by surfactants and the redeployment effect was recognized. However, the quantitative relationship concerning the impact of solids was rarely reported. A batch of biphasic tests were carried out by introducing PYR-1 and hydroxypropyl--cyclodextrin (HPCD) into a mixture of phenanthrene solution and various glass beads (GB37-63, GB105-125, and GB350-500). The comparative results demonstrated that HPCD had little effect on microbial growth and was not degradable by bacterium. A model was proposed to describe the biodegradation process. The regression results indicated that the partition coefficient (1.234, 0.726 and 0.448 L·g) and the degradation rate (0 mmol·L: 0.055, 0.094, and 0.112; 20 mmol·L: 0.126, 0.141, and 0.156; 40 mmol·L: 0.141, 0.156 and 0.184 d) were positively and negatively correlated with the calculated total surface area (TSA) of solids, respectively. Degradation enhanced in the presence of HPCD, and the enhancing factor was calculated (20 mmol·L: 15.16, 40.01, and 145.5; 40 mmol·L: 13.29, 37.97, and 138.4), indicating that the impact of solids was significant for the enhancement of biodegradation.

关键词： biphasic biodegradation hydroxypropyl-β -cyclodextrin (HPCD) polycyclic aromatic hydrocarbons (PAHs)

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Anensemble method for data stream classification in the presence of concept drift

Omid ABBASZADEH,Ali AMIRI,Ali Reza KHANTEYMOORI

《信息与电子工程前沿（英文）》 2015年第16卷第12期页码 1059-1068 doi: 10.1631/FITEE.1400398

摘要： One recent area of interest in computer science is data stream management and processing. By ‘data stream’, we refer to continuous and rapidly generated packages of data. Specific features of data streams are immense volume, high production rate, limited data processing time, and data concept drift; these features differentiate the data stream from standard types of data. An issue for the data stream is classification of input data. A novel ensemble classifier is proposed in this paper. The classifier uses base classifiers of two weighting functions under different data input conditions. In addition, a new method is used to determine drift, which emphasizes the precision of the algorithm. Another characteristic of the proposed method is removal of different numbers of the base classifiers based on their quality. Implementation of a weighting mechanism to the base classifiers at the decision-making stage is another advantage of the algorithm. This facilitates adaptability when drifts take place, which leads to classifiers with higher efficiency. Furthermore, the proposed method is tested on a set of standard data and the results confirm higher accuracy compared to available ensemble classifiers and single classifiers. In addition, in some cases the proposed classifier is faster and needs less storage space.

关键词： Data stream Classificaion Ensemble classifiers Concept drift

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Calculation of collision frequency function for aerosol particles in free molecule regime in presence

Xiaowei LUO, Yannick BENICHOU, Suyuan YU

《能源前沿（英文）》 2013年第7卷第4期页码 506-510 doi: 10.1007/s11708-013-0275-5

摘要： The collision frequency function for aerosol particles has already been calculated for the free molecule regime and for the continuum range. The present work, taking into account the influence of internal force fields such as magnetic force, electric force and molecular forces, created by particles themselves, recalculated the collision frequency in the case of particles much smaller than the mean free path of the gas (free molecule regime). Attractive forces increase naturally the collision frequency, while repulsive forces decrease it. The calculation was performed for all types of central forces deriving from a potential, including Coulomb forces and Van der Waals forces.

关键词： aerosol particles collision frequency function coagulation

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Role of water chemistry on estrone removal by nanofiltration with the presence of hydrophobic acids

Xue JIN,Jiangyong HU

《环境科学与工程前沿（英文）》 2015年第9卷第1期页码 164-170 doi: 10.1007/s11783-014-0747-9

摘要： Hydrophobic acid organic matter (HpoA) extracted from treated effluent has been known to improve the rejection of steroid hormone estrone by reverse osmosis (RO) and nanofiltration (NF) membranes. In this study, the effects of solution chemistry (solution pH and ionic strength) on the estrone rejection by NF membrane with the presence of HpoA were systematically investigated. Crossflow nanofiltration experiments show that the presence of HpoA significantly improved estrone rejection at all pH and ionic strength levels investigated. It is consistently shown that the “enhancement effect” of HpoA on estrone rejection at neutral and alkaline pH is attributed to the binding of estrone by HpoA macromolecules via hydrogen bonding between phenolic functional groups in feed solutions, which leads to an increase in molecular weight and appearance of negative charge. The membrane exhibited the best performance in terms of estrone rejection at pH 10.4 (compared to pH 4 and pH 7) as a result of strengthening the electrostatic repulsion between estrone and membrane with the presence of HpoA. At neutral pH level, the ability of HpoA macromolecules to promote estrone rejection became stronger with increasing ionic strength due to their more extended conformation, which created more chances for the association between estrone and HpoA. The important conclusion of this study is that increasing solution pH and salinity can greatly intensify the “enhancement effect” of HpoA. These results can be important for NF application in direct/indirect potable water reuse.

关键词： indirect potable water reuse steroid hormone nanofiltration(NF) rejection water chemistry hydrophobic acids

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Robust cooperation of connected vehicle systems with eigenvalue-bounded interaction topologies in the presence

Keqiang LI, Feng GAO, Shengbo Eben LI, Yang ZHENG, Hongbo GAO

《机械工程前沿（英文）》 2018年第13卷第3期页码 354-367 doi: 10.1007/s11465-018-0486-x

摘要：

This study presents a distributed H-infinity control method for uncertain platoons with dimensionally and structurally unknown interaction topologies provided that the associated topological eigenvalues are bounded by a predesigned range. With an inverse model to compensate for nonlinear powertrain dynamics, vehicles in a platoon are modeled by third-order uncertain systems with bounded disturbances. On the basis of the eigenvalue decomposition of topological matrices, we convert the platoon system to a norm-bounded uncertain part and a diagonally structured certain part by applying linear transformation. We then use a common Lyapunov method to design a distributed H-infinity controller. Numerically, two linear matrix inequalities corresponding to the minimum and maximum eigenvalues should be solved. The resulting controller can tolerate interaction topologies with eigenvalues located in a certain range. The proposed method can also ensure robustness performance and disturbance attenuation ability for the closed-loop platoon system. Hardware-in-the-loop tests are performed to validate the effectiveness of our method.

关键词： automated vehicles platoon distributed control robustness

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Nonlinear dynamic behaviour of a cam mechanism with oscillating roller follower in presence of profile

Walha LASSAAD, Tounsi MOHAMED, Driss YASSINE, Chaari FAKHER, Fakhfakh TAHER, Haddar MOHAMED

《机械工程前沿（英文）》 2013年第8卷第2期页码 127-136 doi: 10.1007/s11465-013-0254-x

摘要：

In this paper we investigate the nonlinear dynamic behaviour of a cam mechanism with oscillating roller follower in presence of defects. The nonlinear developed lumped-mass model includes eight degrees of freedom with two nonlinear hertzian contacts. The first one is located between cam and first roller while the second is between second roller and the sliding rod. The nonlinear dynamic behaviour is described by second order differential equations which are resolved by using the implicit Newmark algorithm combined with the Newton-Raphson iterative scheme. The influence of the cam profile error on the dynamic behaviour is also investigated.

关键词： cam nonlinear behaviour oscillating roller follower profile error

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Process control factors for continuous microbial perchlorate reduction in the presence of zero-valent

ARTHUR Robert D.,TORLAPATI Jagadish,SHIN Kyung-Hee,CHA Daniel K.,YOON Yeomin,SON Ahjeong

《环境科学与工程前沿（英文）》 2014年第8卷第3期页码 386-393 doi: 10.1007/s11783-013-0593-1

摘要： Process control parameters influencing microbial perchlorate reduction via a flow-through zero-valent iron (ZVI) column reactor were investigated in order to optimize perchlorate removal from water. Mixed perchlorate reducers were obtained from a wastewater treatment plant and inoculated into the reactor without further acclimation. Examined parameters included hydraulic residence time (HRT), pH, nutrients requirement, and perchlorate reduction kinetics. The minimum HRT for the system was concluded to be 8 hr. The removal efficiency of 10 mg·L influent perchlorate concentration was reduced by 20%–80% without control to the neutral pH (HRT= 8 hr). Therefore pH was determined to be an important parameter for microbial perchlorate reduction. Furthermore, a viable alternative to pH buffer was discussed. The microbial perchlorate reduction followed the first order kinetics, with a rate constant ( ) of 0.761 hr . The results from this study will contribute to the implementation of a safe, cost effective, and efficient system for perchlorate reduction to below regulated levels.

关键词： perchlorate zero-valent iron (ZVI) microbial reduction hydrogen

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Sorption of tetracycline to sediments and soils: assessing the roles of pH, the presence of cadmium and

Guixiang ZHANG, Xitao LIU, Ke SUN, Ye ZHAO, Chunye LIN

《环境科学与工程前沿（英文）》 2010年第4卷第4期页码 421-429 doi: 10.1007/s11783-010-0265-3

摘要： Batch sorption experiments were conducted to evaluate the sorption behavior of tetracycline (TC, H L) on sediments and soils in the presence and absence of cadmium (Cd), as affected by pH and properties of sediments and soils. The results indicated stronger nonlinearity and higher capacity of TC sorption on sediments than on soils. Sorption of TC also strongly depended on environmental factors and sediment/soil properties. Lower pH facilitated TC sorption through a cation exchange mechanism, which also took place at pH values above 5.5, where TC existed as a zwitterion (H L ) or anions (HL and L ). When pH was above 7, however, ligand-promoted dissolution of TC might occur due to TC weakening the Al-O bond of aluminum oxide and the Fe-O bond of iron oxide. Natural organic matter (NOM) plays a more important role in TC sorption than cation exchange capacity (CEC) and clay contents. The presence of Cd (II) increased TC sorption on both sediments and soils, which resulted from the decrease of equilibrium solution pH caused by Cd exchange with H ions of sediment/soil surfaces. The increase of TC sorption was also related to the formation of TC-Cd complexes, where Cd acted as a bridge between the sediment/soil and TC.

关键词： sorption tetracycline (TC) pH cadmium (Cd) antibiotic

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Elasto-plastic fatigue crack growth analysis of plane problems in the presence of flaws using XFEM

Sachin KUMAR,A. S. SHEDBALE,I. V. SINGH,B. K. MISHRA

《结构与土木工程前沿（英文）》 2015年第9卷第4期页码 420-440 doi: 10.1007/s11709-015-0305-y

摘要： In this paper, elasto-plastic XFEM simulations have been performed to evaluate the fatigue life of plane crack problems in the presence of various defects. The stress-strain response of the material is modeled by Ramberg-Osgood equation. The von-Mises failure criterion has been used with isotropic hardening. The -integral for two fracture modes (mode-I and mode-II) is obtained by decomposing the displacement and stress fields into their symmetric and antisymmetric parts, then individual stress intensity factors are extracted from -integral. The fatigue life obtained by EPFM is found quite close to that obtained by LEFM.

关键词： XFEM von-Mises yield criterion isotropic hardening fatigue crack growth J-integral

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carbon tetrachloride degradation by hydroxylamine in ferrous ion activated calcium peroxide in the presence

Wenchao Jiang, Ping Tang, Zhen Liu, Huan He, Qian Sui, Shuguang Lyu

《环境科学与工程前沿（英文）》 2020年第14卷第2期 doi: 10.1007/s11783-019-1197-1

摘要： Complete CT degradation was achieved by employing HA to CP/Fe(II)/FA process. Quantitative detection of Fe(II) regeneration and HO• production was investigated. Benzoic acid outcompeted FA for the reaction with HO•. CO2•− was the dominant reductive radical for CT removal. Effects of solution matrix on CT removal were conducted. Hydroxyl radicals (HO•) show low reactivity with perchlorinated hydrocarbons, such as carbon tetrachloride (CT), in conventional Fenton reactions, therefore, the generation of reductive radicals has attracted increasing attention. This study investigated the enhancement of CT degradation by the synergistic effects of hydroxylamine (HA) and formic acid (FA) (initial [CT] = 0.13 mmol/L) in a Fe(II) activated calcium peroxide (CP) Fenton process. CT degradation increased from 56.6% to 99.9% with the addition of 0.78 mmol/L HA to the CP/Fe(II)/FA/CT process in a molar ratio of 12/6/12/1. The results also showed that the presence of HA enhanced the regeneration of Fe(II) from Fe(III), and the production of HO• increased one-fold when employing benzoic acid as the HO• probe. Additionally, FA slightly improves the production of HO•. A study of the mechanism confirmed that the carbon dioxide radical (CO2•−), a strong reductant generated by the reaction between FA and HO•, was the dominant radical responsible for CT degradation. Almost complete CT dechlorination was achieved in the process. The presence of humic acid and chloride ion slightly decreased CT removal, while high doses of bicarbonate and high pH inhibited CT degradation. This study helps us to better understand the synergistic roles of FA and HA for HO• and CO2•− generation and the removal of perchlorinated hydrocarbons in modified Fenton systems.

关键词： Calcium peroxide Hydroxylamine Modified Fenton Reactive oxygen species Perchlorinated hydrocarbon

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Preparation of D-lysine by chemical reaction and microbial asymmetric transformation

LIU Yi, JIAO Qingcai, YIN Xiaoxing

《化学科学与工程前沿（英文）》 2008年第2卷第1期页码 40-43 doi: 10.1007/s11705-008-0023-2

摘要： The DL-lysine crystals from the racemization of L-lysine was treated as substrate with AS1.1009 intact cells as biocatalysts to produce crystalline D-lysine with a yield of 56.6% from the reaction mixture after simple purification. In the presence of 0.10 molar equivalent of salicylaldehyde, L-lysine racemization can be completed within 4 h in 1.0 mol/L of NaOH at 100°C. The activation energy of the processes was 62187.86 J/mol. The characteristics of AS1.1009 decarboxylase were studied. Under the conditions of pH 8.0, temperature 37°C, cell concentration 10 g/L, tween-80 0.5 g/L, substrate concentration 30 g/L, and the specific activity of up to 3840 U, L-lysine can be completely degraded by the decarboxylase for 12 h under the optimal conditions.

关键词： substrate temperature specific activity presence decarboxylase

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标题作者时间类型操作

A practical multi-lane factor model of bridges based on multi-truck presence considering lane load disparities

期刊论文

Ozone kinetics of dimethyl sulfide in the presence of water vapor

Haitao WANG

期刊论文

Surface water treatment benefits from the presence of algae: Influence of algae on the coagulation behavior

Yanxia Zhao, Huiqing Lian, Chang Tian, Haibo Li, Weiying Xu, Sherub Phuntsho, Kaimin Shih

期刊论文

Accelerated degradation of orange G over a widepH range in the presence of FeVO

Xiaoxia Ou, Jianfang Yan, Fengjie Zhang, Chunhua Zhang

期刊论文

Impact of solids on biphasic biodegradation of phenanthrene in the presence of hydroxypropyl- β

Zhenyi ZHANG, Chihiro INOUE, Guanghe LI,

期刊论文

Anensemble method for data stream classification in the presence of concept drift

Omid ABBASZADEH,Ali AMIRI,Ali Reza KHANTEYMOORI

期刊论文

Calculation of collision frequency function for aerosol particles in free molecule regime in presence

Xiaowei LUO, Yannick BENICHOU, Suyuan YU

期刊论文

Role of water chemistry on estrone removal by nanofiltration with the presence of hydrophobic acids

Xue JIN,Jiangyong HU

期刊论文

Robust cooperation of connected vehicle systems with eigenvalue-bounded interaction topologies in the presence

Keqiang LI, Feng GAO, Shengbo Eben LI, Yang ZHENG, Hongbo GAO

期刊论文

Nonlinear dynamic behaviour of a cam mechanism with oscillating roller follower in presence of profile

Walha LASSAAD, Tounsi MOHAMED, Driss YASSINE, Chaari FAKHER, Fakhfakh TAHER, Haddar MOHAMED

期刊论文

Process control factors for continuous microbial perchlorate reduction in the presence of zero-valent

ARTHUR Robert D.,TORLAPATI Jagadish,SHIN Kyung-Hee,CHA Daniel K.,YOON Yeomin,SON Ahjeong

期刊论文

Sorption of tetracycline to sediments and soils: assessing the roles of pH, the presence of cadmium and

Guixiang ZHANG, Xitao LIU, Ke SUN, Ye ZHAO, Chunye LIN

期刊论文

Elasto-plastic fatigue crack growth analysis of plane problems in the presence of flaws using XFEM

Sachin KUMAR,A. S. SHEDBALE,I. V. SINGH,B. K. MISHRA

期刊论文

carbon tetrachloride degradation by hydroxylamine in ferrous ion activated calcium peroxide in the presence

Wenchao Jiang, Ping Tang, Zhen Liu, Huan He, Qian Sui, Shuguang Lyu

期刊论文

Preparation of D-lysine by chemical reaction and microbial asymmetric transformation

LIU Yi, JIAO Qingcai, YIN Xiaoxing

期刊论文

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