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关键词

4Pi-SMLM 1

4Pi超分辨显微术 1

CP);符号间干扰(inter symbol interference, ISI);载波间干扰(inter carrier interference 1

Chrestenson谱 1

ICI);最大似然估计(maximum likelihood estimation 1

MLE) 1

OFDM);快速傅立叶变换(Fast Fourier transform, FFT);循环前缀(cyclic prefix 1

isoSTED 1

m值逻辑函数 1

严格雪崩准则 1

互养菌(Syntrophus 1

互营杆菌(Syntrophorhabdaceae) 1

亚甲基蓝 1

假单胞菌 1

像融合;分数阶导数;直觉模糊集;多聚焦图像 1

分子荧光光谱 1

升流式厌氧污泥床(UASB)颗粒污泥 1

参数优选 1

双光子 1

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Probing the redox process of

Rui Lu, Wei Chen, Wen-Wei Li, Guo-Ping Sheng, Lian-Jun Wang, Han-Qing Yu

《环境科学与工程前沿(英文)》 2017年 第11卷 第1期 doi: 10.1007/s11783-017-0905-y

摘要: Fluorescece spectroelectrochemistry is used to probe redox process of benzoquinone. The benzoquinone reduction state has a lower fluorescence quantum efficiency. CVF and DCVF can reveal more information about benzoquinone redox reactions. This method can analyze compounds with fluorescence and electrochemical activities. Quinones are common organic compounds frequently used as model dissolved organic matters in water, and their redox properties are usually characterized by either electrochemical or spectroscopic methods separately. In this work, electrochemical methodology was combined with two fluorescence spectroelectrochemical techniques, cyclic volta- fluorescence spectrometry (CVF) and derivative cyclic volta- fluorescence spectrometry (DCVF), to determine the electrochemical properties of -benzoquinone in dimethyl sulfoxide, an aprotic solution. The CVF results show that the electrochemical reduction of -benzoquinone resulted in the formation of radical anion and dianion, which exhibited a lower fluorescence intensity and red-shift of the emission spectra compared to that of -benzoquinone. The fluorescence intensity was found to vary along with the electrochemical oxidation and reduction of -benzoquinone. The CVF and DCVF results were in good consistence. Thus, the combined method offers a powerful tool to investigate the electrochemical process of -benzoquinone and other natural organic compounds.

关键词: p-Benzoquinone     Electrochemistry     Fluorescence     Spectroelectrochemistry     Derivative cyclic volta fluorescence    

Comparisons of bridges flutter derivatives and generalized ones

Fuyou XU , Zhe ZHANG , Cailiang HUANG , Airong CHEN ,

《结构与土木工程前沿(英文)》 2009年 第3卷 第3期   页码 272-278 doi: 10.1007/s11709-009-0042-1

摘要: The causes of the nonlinearity of self-excited aerodynamic force of bridge are interpreted from such two aspects as amplitude and wind velocity. The concept of “generalized flutter derivative” is proposed, and its physical meaning is illustrated. The graphs of the generalized flutter derivatives of plate and Sutong Bridge section model are plotted. The characteristics of all generalized flutter derivatives are compared and analyzed, and their superiorities are verified. The results indicate that the physical meaning of generalized flutter derivatives are more explicit compared to the traditional ones. It is more convenient to understand the nonlinearity properties of self-excited aerodynamic force of bridge according to the generalized flutter derivatives graphs with the wind velocity as the horizontal coordinate.

关键词: bridge     flutter derivative     generalized flutter derivative     self-excited aerodynamic force     Sutong Bridge    

Online recognition of drainage type based on UV-vis spectra and derivative neural network algorithm

《环境科学与工程前沿(英文)》 2021年 第15卷 第6期 doi: 10.1007/s11783-021-1430-6

摘要:

• UV-vis absorption analyzer was applied in drainage type online recognition.

关键词: Drainage online recognition     UV-vis spectra     Derivative spectrum     Convolutional neural network    

An enhanced damage plasticity model for predicting the cyclic behavior of plain concrete under multiaxial

Mohammad Reza AZADI KAKAVAND, Ertugrul TACIROGLU

《结构与土木工程前沿(英文)》 2020年 第14卷 第6期   页码 1531-1544 doi: 10.1007/s11709-020-0675-7

摘要: Some of the current concrete damage plasticity models in the literature employ a single damage variable for both the tension and compression regimes, while a few more advanced models employ two damage variables. Models with a single variable have an inherent difficulty in accounting for the damage accrued due to tensile and compressive actions in appropriately different manners, and their mutual dependencies. In the current models that adopt two damage variables, the independence of these damage variables during cyclic loading results in the failure to capture the effects of tensile damage on the compressive behavior of concrete and vice-versa. This study presents a cyclic model established by extending an existing monotonic constitutive model. The model describes the cyclic behavior of concrete under multiaxial loading conditions and considers the influence of tensile/compressive damage on the compressive/tensile response. The proposed model, dubbed the enhanced concrete damage plasticity model (ECDPM), is an extension of an existing model that combines the theories of classical plasticity and continuum damage mechanics. Unlike most prior studies on models in the same category, the performance of the proposed ECDPM is evaluated using experimental data on concrete specimens at the material level obtained under cyclic multiaxial loading conditions including uniaxial tension and confined compression. The performance of the model is observed to be satisfactory. Furthermore, the superiority of ECDPM over three previously proposed constitutive models is demonstrated through comparisons with the results of a uniaxial tension-compression test and a virtual test.

关键词: damage plasticity model     plain concrete     cyclic loading     multiaxial loading conditions    

Isogeometric analysis of coupled thermo-elastodynamic problems under cyclic thermal shock

Asghar AMANI DASHLEJEH

《结构与土木工程前沿(英文)》 2019年 第13卷 第2期   页码 397-405 doi: 10.1007/s11709-018-0473-7

摘要: The isogeometric analysis (IGA) method was extended for the solution of the coupled thermo-elastodynamic equations. The dimensionless formulation was accepted in discretization of the uncoupled and coupled thermoelasticity equations and the Generalized Newmark method was used in the time integration procedure. First, the performance of the proposed method was verified against a two-dimensional benchmark example subjected to constant thermal shock with available exact analytical solutions. Then a two-dimensional half-space benchmark example under thermal shock was solved. Finally, cyclic thermal shock (CTS) loading was applied on the half-space problem. The results dedicated that IGA can be used as a suitable approach in the analysis of the general thermomechanical problems.

关键词: isogeometric analysis     coupled thermo-elastodynamic     dynamic analysis     generalized newmark     cyclic thermal shock    

Synthesis and fluorescence behavior of 2,5-diphenyl-1,3,4-oxadiazole-containing bismaleimides and bissuccinimides

Xin ZHANG, Zichen LI

《化学科学与工程前沿(英文)》 2013年 第7卷 第4期   页码 381-387 doi: 10.1007/s11705-013-1359-9

摘要: Bismaleimides bearing 2,5-diphenyl-1,3,4-oxadiazole chromophores at , , position and corresponding saturated bissuccinimides were synthesized. Several synthetic strategies for these bismaleimides were discussed in detail. Almost no or very weak fluorescence was observed for these bismaleimides, however, the bissuccinimides show a strong fluorescence. The effect of molecular geometry on optical behavior and fluorescence quenching mechanism were investigated by UV-vis absorption and fluorescence emission spectroscopy. The electron coupling of ground state of -bismaleimide is stronger than those of - and -bismaleimides. -Bissuccinimide displays increasing fluorescence quantum yields with red shifts of 22–24 nm, compared to -bissuccinimide. Polymerizable C=C bonds play a key role in the intramolecular fluorescence quenching.

关键词: fluorescence     bismaleimide     oxadiazole     succinimide    

Prediction of cyclic large plasticity for prestrained structural steel using only tensile coupon tests

Liang-Jiu JIA, Tsuyoshi KOYAMA, Hitoshi KUWAMURA

《结构与土木工程前沿(英文)》 2013年 第7卷 第4期   页码 466-476 doi: 10.1007/s11709-013-0219-5

摘要: Cold-formed steel members, which experience complicated prestrain histories, are frequently applied in structural engineering. This paper aims to predict cyclic plasticity of structural steels with tensile and compressive prestrain. Monotonic and cyclic tests on hourglass specimens with tensile and compressive prestrain are conducted, and compared with numerical simulations using the Chaboche model. Two approaches are taken in the simulation. The first requires only the monotonic tensile test data from the prestrained steels, and the second requires both the monotonic tensile test data from the virgin steel and the prestrain histories. The first approach slightly overestimates the compressive stress for specimens with tensile prestrain, while the second approach is able to accurately predict the cyclic plasticity in specimens with tensile and compressive prestrain.

关键词: cyclic plasticity     prestrain     Chaboche model     mild steel    

循环双谱及在周期平稳类故障中的应用

苏中元,贾民平,许飞云,胡建中

《中国工程科学》 2006年 第8卷 第9期   页码 57-60

摘要:

论述了未知循环频率的周期平稳信号循环双谱的估计方法;研究了在循环双谱的循环累积量计算中涉及变量的简化存储方法,提出了该变量矩阵是对称阵,通过算法可以三角阵的元素来表述,克服了循环双谱传统估计方法计算量较大的缺陷,提高了运算效率;提出了循环双谱对调相故障信号的分析能力,以及对加性噪声的处理能力,仿真并验证了该方法的有效性,并将其应用于旋转机械状态分析。

关键词: 周期平稳     循环双谱     滞后积    

Experimental research on seismic behavior of recycled concrete frame under varying cyclic loading

SUN Yuedong, XIAO Jianzhuang, ZHOU Deyuan

《结构与土木工程前沿(英文)》 2008年 第2卷 第4期   页码 302-308 doi: 10.1007/s11709-008-0050-6

摘要: A study is conducted on the seismic behavior of one natural concrete frame and two recycled concrete frames with 100% recycled coarse aggregate whose scales are 1:2 entirely, and a comparative study is conducted under low-reversed cyclic lateral loading and different vertical loading. This work aims to estimate the failure mechanism, hysteresis loops, displacement ductility, deterioration of strength and stiffness and energy dissipation of recycled concrete frames under low-reversed cyclic loading as well as the influence of different vertical loading. Analysis on the basis of the experiment proves that it is entirely feasible to apply recycled concrete to practical engineering for the sake of its good seismic behaviors. Theoretical base is provided for further study and practical application of recycled concrete structure.

关键词: different     aggregate     stiffness     practical application     % recycled    

Cyclic behavior of prefabricated reinforced concrete frame with infill slit shear walls

Kui XIAO,Qilin ZHANG,Bin JIA

《结构与土木工程前沿(英文)》 2016年 第10卷 第1期   页码 63-71 doi: 10.1007/s11709-015-0294-x

摘要: A composite structural system consisting of prefabricated reinforced concrete frame with infill slit shear walls (PRCFW), with good ductility, is a new type of earthquake resistant structure. Pseudo-static tests were performed to evaluate the seismic behavior of the PRCFW system. Two one-bay, two-story PRCFW specimens were both built at one-half scale. Additional computational research is also conducted to enhance the nonlinear analytical capabilities for this system. Combined with the concrete damaged plastic (CDP) model provided by finite element program ABAQUS and the constitutive model of concrete proposed by Chinese code, the damage process of the PRCFW structure under cyclic load is simulated. The simulated results show a good agreement with the test data, the dynamic behavior of the PRCFW system can be simulated sufficiently accurate and efficient to provide useful design information. The experimental and numerical study show that this system has the potential to offer good ductility and energy absorption capacity to dissipate input energy, and stiffness adequate for controlling drift for buildings located in earthquake-prone regions.

关键词: slit shear wall     constitutive model     cyclic     seismic     damage    

Synthesis and characterization of 2,5-bis[4-(2-arylvinyl)phenyl]-1,3,4-oxadiazoles with two-photon fluorescence

ZHU Xiaoqin, QIAN Ying, LU Zhifeng

《化学科学与工程前沿(英文)》 2007年 第1卷 第4期   页码 381-384 doi: 10.1007/s11705-007-0069-6

摘要: Four novel 2,5-bis[4-(2-arylvinyl)phenyl]-1,3,4-oxadiazoles that exhibit strong two-photon absorption and enhanced two-photon excited fluorescence were designed and synthesized based on push-core-pull-core-push molecules built from embedding electron-transporting 1,3,4-oxadiazole in aromatic conjugated system through Wittig-Horner reaction. Their chemical structures were determined to show trans-vinylene character according to infrared (IR) and H nuclear magnetic resonance (NMR) spectra. A very effective energy transfer from the excited units to the ?-conjugated bridging unit can enhance the two-photon absorption and two-photon fluorescence.

关键词: 2-arylvinyl     trans-vinylene character     effective     fluorescence     push-core-pull-core-push    

hydrophobic environment triggering reactive fluorescence probe to real-time monitor mitochondrial DNA

《化学科学与工程前沿(英文)》 2022年 第16卷 第1期   页码 92-102 doi: 10.1007/s11705-021-2063-9

摘要: Mitochondrial DNA has a special structure that is prone to damage resulting in many serious diseases, such as genetic diseases and cancers. Therefore, the rapid and specific monitoring of mitochondrial DNA damage is urgently needed for biological recognition. Herein, we constructed an in situ hydrophobic environment-triggering reactive fluorescence probe named MBI-CN. The fluorophore was 2-styrene-1H-benzo[d]imidazole, and malononitrile was introduced as a core into a molecule to initiate the hydrolysis reaction in the specific environment containing damaged mitochondrial DNA. In this design, MBI-CN conjugates to mitochondrial DNA without causing additional damages. Thus, MBI-CN can be hydrolyzed to generate MBI-CHO in an in situ hydrophobic environment with mitochondrial DNA damage. Meanwhile, MBI-CHO immediately emitted a significative fluorescence signal changes at 437 and 553 nm within 25 s for the damaged mitochondria DNA. Give that the specific and rapid response of MBI-CN does not cause additional damages to mitochondrial DNA, it is a potentially effective detection tool for the real-time monitoring of mitochondrial DNA damage during cell apoptosis and initial assessment of cell apoptosis.

关键词: hydrolysis reaction     mitochondrial DNA damage     in situ hydrophobic environment trigger     fluorescence probe     apoptosis    

Carbon dots-based fluorescence sensor for two-photon imaging of pH in diabetic mice

《化学科学与工程前沿(英文)》 2023年 第17卷 第3期   页码 298-306 doi: 10.1007/s11705-022-2212-9

摘要: Herein, a reversible pH fluorescent sensor was developed using caffeic acid as the precursor by one-step solvothermal synthesis method. The carbon dots-based sensor (CA-CDs) exhibited pH-dependent increase in fluorescence intensity and showed linear relationship in the range of pH 6.60 and 8.00. Notably, the fluorescence sensor has a reversible response to pH change. Finally, the CA-CDs has been successfully applied for two-photon imaging of the pH in liver and kidney of diabetic mice. Imaging results showed that the pH value in kidney of diabetic mice was lower than that of the normal mice, while the pH value in liver of diabetic mice was almost the same as that of the normal mice. The present study provides a simple analytical method for pH detection suitable for in vivo.

关键词: carbon dots     two-photon imaging     pH     diabetic mice    

特高含水期分层段周期注采技术研究与实践认识

姜振海

《中国工程科学》 2012年 第14卷 第4期   页码 77-82

摘要:

针对萨北开发区油层沉积特点及特高含水期剩余油分布特点,以水动力学原理为指导,在已有周期注水实践经验的基础上,结合数值模拟进行机理研究,优化周期注采方式及各项参数,引入了分层段交叉注采改变液流方向改善开发效果的做法,在实践中取得了较好的效果。

关键词: 周期注水     周期采油     方式优化     参数优选    

Experimental investigation of the influence on static and cyclic deformation of structural soft clay

CHEN Yunmin, CHEN Yingping, HUANG Bo

《结构与土木工程前沿(英文)》 2007年 第1卷 第4期   页码 422-429 doi: 10.1007/s11709-007-0057-4

摘要: This paper presents the experimental results performed to study the static and cyclic deformation behavior of undisturbed and remolded soft clays sampling from Xiaoshan. The consolidation tests indicated that the vertical strains of

关键词: consolidation     deformation     experimental     undisturbed    

标题 作者 时间 类型 操作

Probing the redox process of

Rui Lu, Wei Chen, Wen-Wei Li, Guo-Ping Sheng, Lian-Jun Wang, Han-Qing Yu

期刊论文

Comparisons of bridges flutter derivatives and generalized ones

Fuyou XU , Zhe ZHANG , Cailiang HUANG , Airong CHEN ,

期刊论文

Online recognition of drainage type based on UV-vis spectra and derivative neural network algorithm

期刊论文

An enhanced damage plasticity model for predicting the cyclic behavior of plain concrete under multiaxial

Mohammad Reza AZADI KAKAVAND, Ertugrul TACIROGLU

期刊论文

Isogeometric analysis of coupled thermo-elastodynamic problems under cyclic thermal shock

Asghar AMANI DASHLEJEH

期刊论文

Synthesis and fluorescence behavior of 2,5-diphenyl-1,3,4-oxadiazole-containing bismaleimides and bissuccinimides

Xin ZHANG, Zichen LI

期刊论文

Prediction of cyclic large plasticity for prestrained structural steel using only tensile coupon tests

Liang-Jiu JIA, Tsuyoshi KOYAMA, Hitoshi KUWAMURA

期刊论文

循环双谱及在周期平稳类故障中的应用

苏中元,贾民平,许飞云,胡建中

期刊论文

Experimental research on seismic behavior of recycled concrete frame under varying cyclic loading

SUN Yuedong, XIAO Jianzhuang, ZHOU Deyuan

期刊论文

Cyclic behavior of prefabricated reinforced concrete frame with infill slit shear walls

Kui XIAO,Qilin ZHANG,Bin JIA

期刊论文

Synthesis and characterization of 2,5-bis[4-(2-arylvinyl)phenyl]-1,3,4-oxadiazoles with two-photon fluorescence

ZHU Xiaoqin, QIAN Ying, LU Zhifeng

期刊论文

hydrophobic environment triggering reactive fluorescence probe to real-time monitor mitochondrial DNA

期刊论文

Carbon dots-based fluorescence sensor for two-photon imaging of pH in diabetic mice

期刊论文

特高含水期分层段周期注采技术研究与实践认识

姜振海

期刊论文

Experimental investigation of the influence on static and cyclic deformation of structural soft clay

CHEN Yunmin, CHEN Yingping, HUANG Bo

期刊论文