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Hygroscopicity of ambient submicron particles in urban Hangzhou, China

Jiachen ZHANG, Lin WANG, Jianmin CHEN, Shengmao FENG, Jiandong SHEN, Li JIAO

《环境科学与工程前沿（英文）》 2011年 第5卷 第3期   页码 342-347 doi: 10.1007/s11783-011-0358-7

摘要： In this study, hygroscopicity of size-segregated ambient submicron particles in urban Hangzhou was studied from 28th December 2009 to 18th January 2010, using a hygroscopicity-tandem differential mobility analyzer (H-TDMA). The submicron particles in Hangzhou showed a minor hygroscopic growth at 73% relative humidity (RH), and then grew significantly between 77% and 82% RH. Monomodal distribution accounted for 90% for 30 nm particles, 17% for 50 nm particles, and less than 7% for particles larger than 50 nm at 82% RH. Deconvolution of the bimodal distribution indicated a less hygroscopic group and a more hygroscopic group, with the fraction of the more hygroscopic group increasing with the initial dry particle size and then remaining almost constant for accumulation mode particles. Our results imply that submicron particles in urban Hangzhou were almost entirely externally mixed, and the hygroscopic properties of ambient particles in urban Hangzhou were mainly a function of their size and chemical composition.

关键词： hygroscopicity     hygroscopic tandem differential mobility analyzer (H-TDMA)     submicron ambient particles     Hangzhou    

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Analyzing the nonlinear vibrational wave differential equation for the simplified model of Tower Cranes

AHMADI,Sayyid H. Hashemi KACHAPI

《机械工程前沿（英文）》 2014年 第9卷 第1期   页码 58-70 doi: 10.1007/s11465-014-0289-7

摘要：

In the current paper, a simplified model of Tower Cranes has been presented in order to investigate and analyze the nonlinear differential equation governing on the presented system in three different cases by Algebraic Method (AGM). Comparisons have been made between AGM and Numerical Solution, and these results have been indicated that this approach is very efficient and easy so it can be applied for other nonlinear equations. It is citable that there are some valuable advantages in this way of solving differential equations and also the answer of various sets of complicated differential equations can be achieved in this manner which in the other methods, so far, they have not had acceptable solutions. The simplification of the solution procedure in Algebraic Method and its application for solving a wide variety of differential equations not only in Vibrations but also in different fields of study such as fluid mechanics, chemical engineering, etc. make AGM be a powerful and useful role model for researchers in order to solve complicated nonlinear differential equations.

关键词： Algebraic Method (AGM)     tower crane     oscillating system     angular frequency    

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Alluvial channel hydrodynamics around tandem piers with downward seepage

Rutuja CHAVAN, Wenxin HUAI, Bimlesh KUMAR

《结构与土木工程前沿（英文）》 2020年 第14卷 第6期   页码 1445-1461 doi: 10.1007/s11709-020-0648-x

摘要： In this paper, we report the turbulent flow structures and the scour geometry around two piers with different diameters. An experiment was conducted on a non-uniform sand bed with two types of tandem arrangements, namely, pier (T1) with a 75 mm front and 90 mm rear, and pier (T2) with a 90 mm front and 75 mm rear, with and without-seepage flows, respectively. A strong wake region was observed behind the piers, but the vortex strength diminished with downward seepage. Streamwise velocity was found to be maximum near the bed downstream of the piers and at the edge of the scour hole upstream of the piers. Quadrant analysis was used to recognize the susceptible region for sediment entrainment and deposition. Upstream of the piers near the bed, the moments, turbulent kinetic energy (TKE), and TKE fluxes were found to decrease with downward seepage, in contrast to those in a plane mobile bed without piers. The reduction percentages of scour depth at the rear pier compared with the front one were approximately 40% for T1 and 60% for T2. Downward seepage also resulted in restrained growth of scouring with time.

关键词： scour     seepage     Strouhal number     tandem arrangement     turbulent characteristics    

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Social media and mobility landscape: Uncovering spatial patterns of urban human mobility with multi source

Yilan Cui, Xing Xie, Yi Liu

《环境科学与工程前沿（英文）》 2018年 第12卷 第5期 doi: 10.1007/s11783-018-1068-1

摘要：

Check-in and survey data are explored to identify personal activity-specific places.

Ways for detecting and moderating sample bias of Weibo check-in data is proposed.

A graphic representation of urban activity intensity in Beijing, China is presented.

The potential application of Weibo check-in data for urban analysis is introduced.

关键词： Social media     Human mobility     Population bias     Sample reconstruction     Data integration    

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Design of tandem genes cluster for isoflavone engineering

Xunli XIA PhD , Guangxiao YANG PhD , Guangyuan HE PhD ,

《医学前沿（英文）》 2009年 第3卷 第3期   页码 292-296 doi: 10.1007/s11684-009-0057-y

摘要： In this paper, a universal effective novel method of constructing tandem genes cluster for isoflavone engineering was reported. A tandem genes cluster () of secondary metabolites of plant isoflavones was constructed by using the chalcone synthase (CHS), chalcone isomerase (CHI), and isoflavone synthase (IFS) (GenBank accession numbers EU526827, EU526829, EU526830) in only one recombination with the pET22b vector. The resulting expression vector pET- was heterogeneously expressed and co-incubated with barrenwort extractions, and the genistein-like component was detected.

关键词： isoflavones engineering     secondary metabolism     tandem genes cluster    

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On the potential of iPhone significant location data to characterize individual mobility for air pollution

《环境科学与工程前沿（英文）》 2022年 第16卷 第5期 doi: 10.1007/s11783-022-1542-7

摘要：

● We evaluated the accuracy of iPhone data in capturing time-activity patterns.

关键词： Air pollution exposure     Human mobility     iPhone     Significant Location     Smartphone data    

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Available energy analysis of new tandem double-capillary tube refrigeration system for refrigerator-freezers

HE Maogang, ZHANG Ying, SONG Xinzhou, ZHANG Jiantao

《能源前沿（英文）》 2008年 第2卷 第1期   页码 36-42 doi: 10.1007/s11708-008-0013-6

摘要： A new tandem double-capillary tube refrigeration system for refrigerator-freezers is proposed. A capillary tube was added between the two evaporators in the fresh and frozen food storage chests to raise the evaporation temperature of the refrigerating chamber, and reduce the heat exchange temperature difference and the available energy loss. Peng-Robinson (P-R) equation of state was adopted to calculate the thermodynamic properties of the refrigerants, and the available energy analysis of the vapor compression refrigeration cycle was programmed to calculate the thermodynamic performances of the new and the conventional refrigeration cycle of the refrigerator-freezer. The calculation results show that the available energy efficiency of the conventional refrigeration cycle of the refrigerator-freezer is 21.20% and 20.57%, respectively when the refrigerant is R12 and R134a, while that of the double-capillary tube refrigeration cycle of the refrigerator-freezer is 23.97% and 23.44%, respectively. By comparison, the available energy efficiency of the new refrigeration system increases by 13.07% and 13.95%, respectively.
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Tuned reactive power dispatch through modified differential evolution technique

S. BISWAS (RAHA), N. CHAKRABORTY

《能源前沿（英文）》 2012年 第6卷 第2期   页码 138-147 doi: 10.1007/s11708-012-0188-8

摘要： This paper explores the capability of modified differential evolution (MDE) technique for solving the reactive power dispatch (RPD) problem. The proposed method is based on the basic differential evolution (DE) technique with a few modifications made into it. DE is one of the strongest optimization techniques though it suffers from the problem of slow convergence while global minima appear. The proposed modifications are tried to resolve the problem. The RPD problem mainly defines loss minimization with stable voltage profile. To solve the RPD problem, the generator bus voltage, transformer tap setting and shunt capacitor placements are controlled by the MDE approach. In this paper, IEEE 14-bus and IEEE 30-bus systems are chosen for MDE implementation. The applied modification show much improved result in comparison to normal DE technique. Comparative study with other soft-computing technique including DE validates the effectiveness of the proposed method.

关键词： reactive power dispatch (RPD)     modified differential evolution (MDE)     differential evolution algorithm with localizations around the best vector (DELB)    

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A visual graphic approach for mobility analysis of parallel mechanisms

Xu PEI, Jingjun YU

《机械工程前沿（英文）》 2011年 第6卷 第1期   页码 92-95 doi: 10.1007/s11465-011-0213-3

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微观移动协议主动切换机制研究

赵阿群

《中国工程科学》 2004年 第6卷 第8期   页码 50-56

摘要：

针对微观移动协议现有切换机制的缺点，提出了主动切换机制，利用移动预测技术，在切换发生前预测移动主机将要切换的下一蜂窝以及切换的时刻，为移动主机预先建立新路径；为了保证主动切换机制的实现，提出了一个适用于主动切换机制并易于实现的移动预测算法；同时还提出了主动切换过程中分组丢失和重复避免方法；通过理论分析和系统仿真的方法对主动切换机制进行了性能评价，结果表明主动切换机制以较小的代价获得了可观的性能改善。

关键词： 微观移动协议     主动切换机制     移动预测     性能评价    

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quantification of several classes of antibiotics in water, sediments, and fish muscles by liquid chromatography–tandem

WEI Yimei,ZHANG Yuan,XU Jian,GUO Changsheng,LI Lei,FAN Wenhong

《环境科学与工程前沿（英文）》 2014年 第8卷 第3期   页码 357-371 doi: 10.1007/s11783-013-0580-6

摘要： Precise and sensitive methods for the simultaneous determination of different classes of antibiotics, including sulphonamides, fluoroquinolones, macrolides, tetracyclines, and trimethoprim in surface water, sediments, and fish muscles were developed. In water samples, drugs were extracted with solid-phase extraction (SPE) by passing 1000 mL of water through hydrophilic lipophilic balanced (HLB) SPE cartridges. Sediment samples were solvent-extracted, followed by tandem SPE (strong anion exchange (SAX) + HLB) clean-ups. Fish muscles were extracted by a mixture of acetonitrile and citric buffer (80:20, v/v) solution, and cleaned by SPE. Liquid chromatography–tandem mass spectrometry (LC-MS/MS) with multiple reaction monitoring (MRM) detection was employed to quantify all compounds. The recoveries for the antibiotics in the spiked water, sediment, and fish samples were 60.2%–95.8%, 48.1%–105.3%, and 59.8%–103.4%, respectively. The methods were applied to samples taken from Dianchi Lake, China. It showed that concentrations of the detected antibiotics ranged from limits of quantification (LOQ) to 713.6 ng·L (ofloxacin) in surface water and from less than LOQ to 344.8 μg·kg (sulphamethoxazole) in sediments. The number of detected antibiotics and the overall antibiotic concentrations were higher in the urban area than the rural area, indicating the probable role of livestock and human activities as important sources of antibiotic contamination. In fish muscles, the concentration of norfloxacin was the highest (up to 38.5 μg·kg ), but tetracyclines and macrolides were relatively low. Results showed that the methods were rapid and sensitive, and capable of determining several classes of antibiotics from each of the water, sediment, and fish matrices in a single run.

关键词： antibiotics     liquid chromatography–tandem mass spectrometry (LC-MS/MS)     water     sediment     fish muscle    

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Analysis of the kinematic characteristics of a high-speed parallel robot with Schönflies motion: Mobility

Fugui XIE,Xin-Jun LIU

《机械工程前沿（英文）》 2016年 第11卷 第2期   页码 135-143 doi: 10.1007/s11465-016-0389-7

摘要：

This study introduces a high-speed parallel robot with Schönflies motion. This robot exhibits a promising prospect in realizing high-speed pick-and-place manipulation for packaging production lines. The robot has four identical limbs and a single platform. Its compact structure and single-platform concept provides this robot with good dynamic response potential. A line graph method based on Grassmann line geometry is used to investigate the mobility characteristics of the proposed robot. A generalized Blanding rule is also introduced into this procedure to realize mutual conversion between the line graphs for motions and constraints. Subsequently, the inverse kinematics is derived, and the singularity issue of the robot is investigated using both qualitative and quantitative approaches. Input and output transmission singularity indices are defined based on the reciprocal product in screw theory and the virtual coefficient by considering motion/force transmission performance. Thereafter, the singular loci of the proposed robot with specific geometric parameters are derived. The mobility analysis, inverse kinematics modeling, and singularity analysis conducted in this study are helpful in developing the robot.

关键词： parallel robot     mobility     inverse kinematics     singularity     transmission performance    

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Review of MEMS differential scanning calorimetry for biomolecular study

Shifeng YU, Shuyu WANG, Ming LU, Lei ZUO

《机械工程前沿（英文）》 2017年 第12卷 第4期   页码 526-538 doi: 10.1007/s11465-017-0451-0

摘要：

Differential scanning calorimetry (DSC) is one of the few techniques that allow direct determination of enthalpy values for binding reactions and conformational transitions in biomolecules. It provides the thermodynamics information of the biomolecules which consists of Gibbs free energy, enthalpy and entropy in a straightforward manner that enables deep understanding of the structure function relationship in biomolecules such as the folding/unfolding of protein and DNA, and ligand bindings. This review provides an up to date overview of the applications of DSC in biomolecular study such as the bovine serum albumin denaturation study, the relationship between the melting point of lysozyme and the scanning rate. We also introduce the recent advances of the development of micro-electro-mechanic-system (MEMS) based DSCs.

关键词： differential scanning calorimetry     biomolecule     MEMS     thermodynamic    

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Erratum to: On the potential of iPhone significant location data to characterize individual mobility

《环境科学与工程前沿（英文）》 2022年 第16卷 第9期 doi: 10.1007/s11783-022-1556-1

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PM-support interfacial effect and oxygen mobility in Pt, Pd or Rh-loaded (Ce,Zr,La)O catalysts

《环境科学与工程前沿（英文）》 2021年 第15卷 第4期 doi: 10.1007/s11783-020-1369-z

摘要：

• Pt/CZL exhibits the optimum catalytic performance for HC and NOx elimination.

关键词： Precious metal-loaded (Ce     Zr     La)O2 catalysts     Oxygen mobility     Catalytic performance    

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标题 作者 时间 类型 操作

Hygroscopicity of ambient submicron particles in urban Hangzhou, China

Jiachen ZHANG, Lin WANG, Jianmin CHEN, Shengmao FENG, Jiandong SHEN, Li JIAO

期刊论文

Analyzing the nonlinear vibrational wave differential equation for the simplified model of Tower Cranes

AHMADI,Sayyid H. Hashemi KACHAPI

期刊论文

Alluvial channel hydrodynamics around tandem piers with downward seepage

Rutuja CHAVAN, Wenxin HUAI, Bimlesh KUMAR

期刊论文

Social media and mobility landscape: Uncovering spatial patterns of urban human mobility with multi source

Yilan Cui, Xing Xie, Yi Liu

期刊论文

Design of tandem genes cluster for isoflavone engineering

Xunli XIA PhD , Guangxiao YANG PhD , Guangyuan HE PhD ,

期刊论文

On the potential of iPhone significant location data to characterize individual mobility for air pollution

期刊论文

Available energy analysis of new tandem double-capillary tube refrigeration system for refrigerator-freezers

HE Maogang, ZHANG Ying, SONG Xinzhou, ZHANG Jiantao

期刊论文

Tuned reactive power dispatch through modified differential evolution technique

S. BISWAS (RAHA), N. CHAKRABORTY

期刊论文

A visual graphic approach for mobility analysis of parallel mechanisms

Xu PEI, Jingjun YU

期刊论文

微观移动协议主动切换机制研究

赵阿群

期刊论文

quantification of several classes of antibiotics in water, sediments, and fish muscles by liquid chromatography–tandem

WEI Yimei,ZHANG Yuan,XU Jian,GUO Changsheng,LI Lei,FAN Wenhong

期刊论文

Analysis of the kinematic characteristics of a high-speed parallel robot with Schönflies motion: Mobility

Fugui XIE,Xin-Jun LIU

期刊论文

Review of MEMS differential scanning calorimetry for biomolecular study

Shifeng YU, Shuyu WANG, Ming LU, Lei ZUO

期刊论文

Erratum to: On the potential of iPhone significant location data to characterize individual mobility

期刊论文

PM-support interfacial effect and oxygen mobility in Pt, Pd or Rh-loaded (Ce,Zr,La)O catalysts

期刊论文