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Absorption,fluorescence and resonance Rayleigh scattering spectra of hydrophobic hydrogen bonding of eosin Y/Triton X-100 nanoparticles and their analytical applications

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Science China Chemistry 2010年第11期53卷 2363-2372页

作者： Ling Kong ZhongFang Liu XiaoLi Hu shaopu Liu Southwest Univ Sch Chem & Chem Engn Minist Educ Key Lab Luminescence & Real Time Anal Chongqing 400715 Peoples R China

In a weak acidic medium(pH 2.4-2.8),eosin Y molecules(H2L) could replace water molecules to associate with Triton X-100 to form hydrophobic hydrogen bonding *** complexes could further aggregate to form nanoparticles through the squeezing action of the water phase and Van Der Waals force,resulting in changes in the absorption spectrum and fluorescence quenching of EY as well as the significant enhancement of resonance Rayleigh *** enables the sensitive determination of Triton X-100 using the fading spectrophotometry,fluorescence quenching method and RRS *** them,the RRS method shows the highest sensitivity with a detection limit of 20.6 ng mL-1 for Triton *** optimum experimental conditions and factors that affect the absorption,fluorescence and RRS spectra were *** effects of coexisting substances were investigated and the results showed good *** on these results,new spectrophotometric methods,fluorescence quenching method and RRS method for the determination of Triton X-100,were *** hydrogen bonding association of eosin Y with Triton X-100 and the formation of nanoparticles as well as their effects on related spectral characteristics were discussed utilizing infrared,transmission electron microscope technique and quantum chemical method.

关键词： eosin Y Triton X-100 resonance Rayleigh scattering fluorescence quenching absorption spectrum

Effect of Fast Cooling Rate on the Microstructure and Mechanical Properties of Low-Carbon High-Strength Steel Annealed in the Intercritical Region

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Journal of Wuhan University of Technology(Materials Science) 2014年第3期29卷 572-577页

作者：李壮田勇 KANG shaopu ZHENG Zhen LIU Ming School of Materials Science and Engineering Shenyang Aerospace University State Key Lab of Rolling and Automation Northeastern University

The effect of fast cooling rate on the microstructure and mechanical properties of low-carbon high-strength steel annealed in the intercritical region was investigated using a Gleeble 1500 thermomechanical simulator and a continuous annealing thermomeehanical simulator. The results showed that the microstructure consisted of ferrite and bainite as the main phases with a small amount of retained austenite and martensite islands at cooling rate of 5 and 50 ℃/s, respectively. Fast cooling after continuous annealing affected all constituents of the microstructure. The mechanical properties were improved considerably. Ultimate tensile strength （U-TS） increased and total elongation （TEL） decreased with increasing cooling rate in all specimens. The specimen 1 at a cooling rate of 5 ℃/s exhibited the maximum TEL and UTSxTEL （20% and 27 200 MPa%, respectively） because of the competition between weakening by presence of the retained austenite plus the carbon indigence by carbide precipitation, and strengthening by martensitic islands and precipitation. The maximum UTS and YS （1 450 and 951 MPa, respectively） were obtained for specimen 2 at a cooling rate of 50 ℃/s. This is attributed to the effect of dispersion strengthening of finer martensite islands and the effect of precipitation strengthening of carbide precipitates.

关键词： cooling rate low-carbon high-strength steel intercritical annealing microstructure mechanical properties

Study on the interaction between diphenhydramine and erythrosin by absorption,fluorescence and resonance Rayleigh scattering spectra

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Science China Chemistry 2007年第1期50卷 54-62页

作者： TANG XiaoLing LIU ZhongFang LIU shaopu HU XiaoLi School of Chemistry and Chemical Engineering Southwest China UniversityChongqing 400715China

In pH 4.5 Britton-Robinson(BR)buffer solution,erythrosin(ET)can react with diphenhydramine(DP)to form a 1:1 ion-association complex,which not only results in the change of the absorption spectra,but also results in the great enhancement of resonance Rayleigh scattering(RRS)and the quenching of ***,a new RRS spectrum will appear,and the maximum RRS wavelength was located at about 580 *** this work,the spectral characteristics of the absorption,fluorescence and RRS,the optimum conditions of the reaction and the properties of an analytical chemistry were inves- tigated.A sensitive,simple and new method for the determination of DP by using erythrosin as a probe has been *** detection limits for DP were 0.0020μg/mL for RRS method,0.088μg/mL for absorption method and 0.094μg/mL for *** was a linear relationship between the absorbance,RRS and fluorescence intensities and the drug concentration in the range of 0.0067-2.0, 0.29-6.4 and 0.31-3.2μg/mL,*** effects of the interaction of diphenhydramine and erythrosin on the absorption,fluorescence and resonance Rayleigh scattering spectra were discussed. In light polarization experiment,the polarization of RRS at maximum wavelength was measured to be P =0.9779,and it revealed that the RRS spectrum of DP-ET complex consists mostly of resonance scat- tering and few resonance *** this study,enthalpy of formation and mean polarizability were calculated by AM1 quantum chemistry *** addition,the reaction mechanism and the rea- sons for the enhancement of scattering spectra and the energy transfer between absorption,fluores- cence and RRS were discussed.

关键词： resonance Rayleigh scattering spectrophotometry fluorescence quenching method diphenhydramine erythrosin

Influence of vehicle-road coupled vibration on tire adhesion based on nonlinear foundation

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Applied Mathematics and Mechanics(English Edition) 2021年第5期42卷 607-624页

作者： Junning ZHANG shaopu YANG Shaohua LI Yongjie LU Hu DING School of Traffic and Transportation Shijiazhuang Tiedao UniversityShijiazhuang 050043China State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang 050043China Shanghai Institute of Applied Mathematics and Mechanics Shanghai Key Laboratory of Mechanics in Energy EngineeringShanghai UniversityShanghai 200072China

The influence of pavement vibration on tire adhesion is of great significance to the structure design of vehicle and *** adhesion between tire and road is the key to studying vehicle dynamics,and the precise description of tire adhesion affects the accuracy of dynamic vehicle ***,in most models,only road roughness is considered,and the pavement vibration caused by vehicle-road interaction is *** this paper,a vehicle is simplified as a spring-mass-damper oscillator,and the vehicle-pavement system is modeled as a vehicle moving along an Euler-Bernoulli beam with finite length on a nonlinear *** road roughness is considered as a sine wave,and the shear stress is ignored on the *** to the contact form between tire and road,the LuGre tire model is established to calculate the tire adhesion *** Galerkin method is used to simplify the partial differential equations of beam vibration into finite ordinary differential equations.A product-to-sum formula and a Dirac delt function are used to deal with the nonlinear term caused by the nonlinear foundation,which realizes the fast and accurate calculation of super-high dimensional nonlinear ordinary differential *** addition,the dynamic responses between the coupled system and the traditional uncoupled system are compared with each *** obtained results provide an important theoretical basis for research on the influence of vehicle-road coupled vibration on tire adhesion.

关键词： vehicle system dynamics vehicle-road coupled vibration LuGre tire model Galerkin method

Absorption, fluorescence and resonance Rayleigh scattering spectral characteristics of interaction of gold nanoparticle with safranine T

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Science China Chemistry 2005年第3期48卷 216-226页

作者： HE Youqiu LIU shaopu LIU Qin LIU Zhongfang HU Xiaoli Chemistry and Chemical Engineering College Southwest China Normal University Chongqing 400715 China Chemistry and Chemical Engineering College Southwest China Normal University Chongqing 400715 China Chemistry and Chemical Engineering College Southwest China Normal University Chongqing 400715 China Chemistry and Chemical Engineering College Southwest China Normal University Chongqing 400715 China Chemistry and Chemical Engineering College Southwest China Normal University Chongqing 400715 China

The interaction between gold nanoparticle and safranine T (ST) has been studied with resonance Rayleigh scattering (RRS) spectra, absorption and fluorescence spectra. In the pH 5 solution, citrate [(H2L)2?] self-assembles on the surface of positively-charged gold nanopar-ticle, which results in the [(Au)n(H2L)m]x? complex. In other words, one of carboxylate oxygens in (H2L)2? moves inward and combines with gold nanoparticle. The other carboxylate oxygens moves outward to form a supermolecular complex anion with x negative charges. Then by virtue of electrostatic attraction, hydrophobic force and charge transfer action, the complex anion binds with ST cation to form a new ion-association complex. Here (H2L)2? acts as a bridge. The forma-tion of the complex results in the significant enhancement of RRS intensity, the appearance of new RRS spectrum, the red shift of plasma absorption band of gold nanoparticle as well as the decrease in the absorbance and fluorescence quenching for safranine T. In this work, the inter-action between gold nanoparticle and ST on the RRS, absorption and fluorescence spectra has been investigated. The reason why RRS intensity increases greatly and the reaction mechanism have been inquired. The results show that RRS spectra can not only be used to study nanopar-ticle and reaction product, but also are a sensitive means to characterize and detect nanoparti-cles.

关键词： gold nanoparticle, resonance Rayleigh scattering spectra, fluorescence quenching, absorption spectra, safranine T.

Dimension reduction graph-based sparse subspace clustering for intelligent fault identification of rolling element bearings

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International Journal of Mechanical System Dynamics 2021年第2期1卷 207-219页

作者： Le Zhao shaopu Yang Yongqiang Liu State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao UniversityShijiazhuangHebeiChina School of Traffic and Transportation Shijiazhuang Tiedao UniversityShijiazhuangHebeiChina

Sparse subspace clustering(SSC)is a spectral clustering *** high-dimensional data are often dispersed over the union of many low-dimensional subspaces,their representation in a suitable dictionary is ***,SSC is an effective technology for diagnosing mechanical system *** main purpose is to create a representation model that can reveal the real subspace structure of high-dimensional data,construct a similarity matrix by using the sparse representation coefficients of high-dimensional data,and then cluster the obtained representation coefficients and similarity matrix in ***,the design of SSC algorithm is based on global expression in which each data point is represented by all possible cluster data *** leads to nonzero terms in nondiagonal blocks of similar matrices,which reduces the recognition performance of *** improve the clustering ability of SSC for rolling bearing and the robustness of the algorithm in the presence of a large number of background noise,a simultaneous dimensionality reduction subspace clustering technology is provided in this *** the feature extraction of envelope signal,the dimension of the feature matrix is reduced by singular value decomposition,and the Euclidean distance between samples is replaced by correlation distance.A dimension reduction graph-based SSC technology is *** and bearing data of Western Reserve University show that the proposed algorithm can improve the accuracy and compactness of clustering.

关键词： correlation distance dimension reduction sparse subspace clustering

Resonance Rayleigh scattering spectrum for the chelate of lanthanum(Ⅲ) with sodium tanshinon ⅡA silate and its analytical application

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Science China Chemistry 2006年第5期49卷 423-429页

作者： PENG Jingdong LIU shaopu LIU Zhongfang SHI Yan College of Chemistry and Chemical Engineering Southwest China Normal University Chongqing 400715 China College of Chemistry and Chemical Engineering Southwest China Normal University Chongqing 400715 China College of Chemistry and Chemical Engineering Southwest China Normal University Chongqing 400715 China College of Chemistry and Chemical Engineering Southwest China Normal University Chongqing 400715 China

In a pH 3.6―5.0 HAc-NaAc buffer solution, when sodium tanshinon ⅡA silate (STSⅡA) reacts with La(Ⅲ) to form a chelate, the resonance Rayleigh scattering (RRS) intensity can be en-hanced greatly and a new RRS spectrum will appear. The maximum RRS peak is located at 306 nm and the RRS intensity is proportional to the concentration of STSⅡA in a certain range. The method is very sensitive and the detection limit for STSⅡA (3σ/K) is 82.12 ng·mL?1. The optimum reaction condi-tions and the effect of coexisting substances have been investigated. A new, simple and fast method for the determination of STSⅡA based on RRS method is developed. It can be applied to the deter-mination of STSⅡA in the synthesis samples and Nuoxinkang injection. Combined with infrared ab-sorption and NMR spectra, the structure of the chelate and the reasons of RRS enhancement are also discussed.

关键词： lanthanum(Ⅲ), sodium tanshinon ⅡA silate, chelate, resonance Rayleigh scattering, analytical application.

Study on the interaction between palladium(II)-chlorpromazine hydrochloride and sodium tungstate by the resonance Rayleigh scattering, second-order scattering and frequency doubling scattering spectra and its analytical application

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Science China Chemistry 2011年第3期54卷 506-514页

作者： CHEN PeiLi LIU shaopu LIU ZhongFang HU XiaoLi LI CuiXia Key Laboratory on Luminescence and Real-Time Analysis Ministry of EducationSchool of Chemistry and Chemical EngineeringSouthwest UniversityChongqing 400715China

The interaction between palladium(II)-chlorpromazine hydrochloride and sodium tungstate was investigated by ultravioletvisible absorption,resonance Rayleigh scattering(RRS),second-order scattering(SOS)and frequency doubling scattering (FDS)*** pH 5.3 Britton-Robinson(BR)buffer medium,chlorpromazine hydrochloride(CPZ)reacted with Pd(II) to form 2:1 cationic chelate,which further reacted with Na2WO4 to form a 1:1 ternary ion-association complex ([Pd(CPZ)2]·WO4).As a result,the signal intensities of RRS,SOS and FDS were enhanced greatly,and the enhancements of scattering were proportional to the CPZ concentration in a certain *** maximum wavelengths were located at 310 nm, 570 nm and 391 nm,respectively and the detection limits(3)were 1.6 ng/mL(RRS method),3.2 ng/mL(SOS method)and 5.6 ng/mL(FDS method).The optimum reaction conditions,the influences of coexisting substances and analytical application were mainly investigated by RRS method due to its highest sensitivity.A highly sensitive,simple,rapid and new method had been proposed to determine CPZ in the pharmaceutical form and residue of CPZ in *** addition,the Gibbs free energy change(△Gf)of ion-association reaction was computed by using B3LYP/3-21g*/LanL2dz *** formation of ion-association and the reasons for the enhancement of RRS were also discussed.

关键词： resonance Rayleigh scattering second-order scattering frequency doubling scattering chlorpromazine hydrochloride palladium(II) Na2WO4

Special characteristics of fluorescence and resonance Rayleigh scattering for cadmium telluride nanocrystal aqueous solution and its interactions with aminoglycoside antibiotics

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Science China Chemistry 2009年第1期52卷 76-85页

作者： LI TaiShan LIU shaopu LIU ZhongFang HU XiaoLi ZHANG LiPing School of Chemistry and Chemical Engineering Southwest UniversityChongqing 400715China Tangshan Environmental Monitoring Center Tangshan 063000China Hebei Energy Institute of Vocation and Technology Tangshan 063000China

CdTe nanocrystals(CdTe NCs) were achieved by reaction of CdCl2 with KHTe solution and were capped with sodium *** product was detected by transmission electron microscopy(TEM),high-resolution transmission electron microscopy(HRTEM),energy dispersive spectroscopy(EDS),fluorescence spectra,ultraviolet-visible spectra and X-ray diffraction(XRD).The CdTe NCs are of cubic structure and the average size is about 5 *** fluorescence quantum yield of CdTe NCs aqueous solution increased from 37% to 97% after 20 d under room *** maximum λem of fluorescence changed from 543 nm to 510 nm and the blue shift was 33 *** NCs aqueous solution can be steady for at least 10 months at 4℃ in a *** resonance Rayleigh scattering(RRS) of CdTe NCs in the aqueous solution was *** maximum scattering peak was located at about 554 *** interactions of CdTe NCs with amikacin sulfate(AS) and micronomicin sulfate(MS) were investigated *** effects of AS and MS on fluorescence and RRS of CdTe NCs were *** was found that AS and MS quenched the photoluminescence of CdTe NCs and enhanced RRS of CdTe *** optimum conditions,there are linear relationships between quenching intensity(F0-F),intensity of RRS(I-I0) and concentration of AS and *** detection limits(3б) of AS and MS are respectively 3.4 ng·mL-1 and 2.6 ng·mL-1 by the fluorescence quenching method,and 15.2 ng·mL-1 and 14.0 ng·mL-1 by the RRS *** methods have high sensitivity,thus CdTe NCs may be used as fluorescence probes and RRS probes for the detection of aminoglycoside antibiotics.

关键词： CdTe nanocrystal fluorescence characteristics resonance Rayleigh scattering amikacin sulfate micronomicin sulfate