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Discordant patterns of genetic variation between mitochondrial and microsatellite markers in Acanthogobius ommaturus across the coastal areas of China

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Acta Oceanologica Sinica 2023年第4期42卷 72-80页

作者： Chenyu song Zhong Tu Na song Key Laboratory of Mariculture(Ocean University of China) Ministry of EducationQingdao 266003China Shandong Fisheries Development and Resources Conservation Center Yantai 264003China

Acanthogobius ommaturus, which belongs to the family Gobiidae, is a euryhaline and demersal fish that is widely distributed in the coastal areas, harbors, and estuaries of China, D. P. R. Korea and Japan. In this study, the genetic diversity and genetic structure of five geographical populations of A. ommaturus was assessed using the mitochondrial hypervariable region gene and microsatellite markers. The results of the two genetic markers indicated that the A. ommaturus populations had a high level of genetic diversity. The mitochondrial marker detected weak genetic differentiation among populations, and the Neighbor-Joining tree showed that there was no obvious pedigree branches and geographic structure as well. However, population of Zhoushan showed significant genetic differentiation with other populations by microsatellite markers. The population of *** has not experienced bottleneck effect recently. We speculated that the Pleistocene climate change and juvenile fish dispersal played an important role in the population differentiation of A. ommaturus.

关键词： mitochondrial markers microsatellite markers genetic diversity genetic structure Acanthogobius ommaturus

Dynamic property tests of frozen red sandstone using a split hopkinson pressure bar

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Earthquake Engineering and Engineering Vibration 2019年第3期18卷 511-519页

作者： Shan Renliang song Yongwei song Liwei Bai Yao Institute of Mechanics and Civil Engineering China University of Mining and TechnologyBeijing

In this study, frozen red sandstone specimens were impacted by a Split Hopkinson bar (SHPB), with a velocity of 4.558 ~ 6.823 ms-1. The temperature of the specimens was maintained at -15℃ during the experiment. For comparison purposes, static uniaxial compression tests were conducted in advance using a freezing triaxial test machine. Four stress-strain curves were obtained in diff erent average strain rates. The test results suggested that when the average strain rate is low, the specimen strength changes gradually;but when it is high, its strength changes rapidly. When the average strain rate is 120.73 s-1, the peak value of stress is as high as 82.96 MPa, which is about two times that of the static compressive strength of 44.1 MPa. A constitutive model was established that was composed of the damaged, viscoelastic and spring bodies, and revealed the variations of compressive strength and strain for the frozen red sandstone under diff erent high strain rates. The test results also showed that the failure form was correlated to the average strain rate of the frozen red sandstone. When the average strain rate is low, the damage was only distributed on the specimen’s edges. However, as the average strain rate increases, the damage range extended to the central parts of the specimen. When the average strain rate reached 107.34s-1, the specimen was smashed.

关键词： SHPB negative temperature frozen red sandstone dynamic compressive strength constitutive model

Nondestructive Testing and Characterization of Residual Stress Field Using an Ultrasonic Method

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Chinese Journal of Mechanical Engineering 2016年第2期29卷 365-371页

作者： song Wentao XU Chunguang PAN Qinxue song Jianfeng School of Mechanical Engineering Beijing Institute of Technology School of Mechanical Engineering Shijiazhuang Tiedao University

To address the difficulty in testing and calibrating the stress gradient in the depth direction of mechanical components, a new technology of nondestructive testing and characterization of the residual stress gradient field by ultrasonic method is proposed based on acoustoelasticity theory. By carrying out theoretical analysis, the sensitivity coefficients of different types of ultrasonic are obtained by taking the low carbon steel（12%C） as a research object. By fixing the interval distance between sending and receiving transducers, the mathematical expressions of the change of stress and the variation of time are established. To design one sending-one receiving and oblique incidence ultrasonic detection probes, according to Snell law, the critically refracted longitudinal wave（LCR wave） is excited at a certain depth of the fixed distance of the tested components. Then, the relationship between the depth of LCR wave detection and the center frequency of the probe in Q235 steel is obtained through experimental study. To detect the stress gradient in the depth direction, a stress gradient LCR wave detection model is established, through which the stress gradient formula is derived by the relationship between center frequency and detecting depth. A C-shaped stress specimen of Q235 steel is designed to conduct stress loading tests, and the stress is measured with the five group probes at different center frequencies. The accuracy of ultrasonic testing is verified by X-ray stress analyzer. The stress value of each specific depth is calculated using the stress gradient formula. Accordingly, the ultrasonic characterization of residual stress field is realized. Characterization results show that the stress gradient distribution is consistent with the simulation in ANSYS. The new technology can be widely applied in the detection of the residual stress gradient field caused by mechanical processing, such as welding and shot peening.

关键词： ultrasonic nondestructive testing acoustoelasticity theory residual stress field stress gradient ultrasonic characterization

Cell vibron polariton resonantly self-confined in the myelin sheath of nerve

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Nano Research 2020年第1期13卷 38-44页

作者： Bo song Yousheng Shu School of Optical-Electrical Computer Engineering University of Shanghai for Science and TechnologyShanghai200093China State Key Laboratory of Medical Neurobiology Institute for Translational Brain ResearchMOE Frontiers Center for Brain ScienceDepartment of NeurologyHuashan HospitalFudan UniversityShanghai200032China

Polaritons are arousing tremendous interests in physics and material sciences for their unique and amazing properties,especially including the condensation,lasing without inversion and even room-temperature ***,we propose a cell vibron polariton(cell-VP):a collectively coherent mode of a photon and all phospholipid molecules in a myelin sheath formed by glial ***-VP can be resonantly self-confined in the myelin sheath under physiological *** observations benefit from the specifically compact,ordered and polar thin-film structure of the sheath,and the relatively strong coupling of the mid-infrared photon with the vibrons of phospholipid tails in the *** underlying physics is revealed to be the collectively coherent superposition of the photon and vibrons,the polariton induced significant enhancement of myelin permittivity,and the resonance of the polariton with the *** captured cell-VPs in myelin sheaths may provide a promising way for super-efficient consumption of extra-weak bioenergy and even directly serve for quantum *** findings further the understanding of nervous system operations at cellular level from the view of quantum mechanics.

关键词： cell polariton nerves myelin sheath quantum state

Microwave-assisted synthesis of nanoscale Eu(BTC)(H_2O)·DMF with tunable luminescence

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Science China Chemistry 2015年第6期58卷 973-978页

作者： song Dang Shuyan song Jing Feng Hongjie Zhang State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied Chemistry Chinese Academy of Sciences

Nanoscale europium（Ⅲ） metal-organic frameworks, Eu（BTC）（H20）.DMF, were synthesized by rapid microwave-assisted method. The components of the as-prepared products were confirmed by the elemental analysis, X-ray powder diffraction （XRD）, thermal gravimetric analysis （TGA） and Fourier-transform infrared spectra （FTIR） analyses. Eu（BTC）（H20）.DMF with various morphologies, including particle-like, rod-like, straw-sheaf-like nanostructures, could be simply prepared by con- trolling the concentrations of the starting reactants. The optical measurements on the obtained Eu（BTC）（H20）- DMF indicated that all the nanomaterials show the characteristic emissions of the Eu3＋ ions at 578, 590, 612, 650, and 699 nm, which were at- tributed to 5Do→7FJ （J=0-4） transitions of the Eu3＋ ion, respectively. It was also noticed that the luminescent properties of the as-prepared products were heavily dependent on the morphologies and sizes of the nanomaterials. The assembled straw-sheaf-like architectures displayed the strongest emissions and the longest luminescence lifetime, which was mainly due to the fewest surface defects.

关键词： metal-organic frameworks nanomateriais europium luminescence microwave-assisted synthesis

Galerkin approximation with Legendre polynomials for a continuous-time nonlinear optimal control problem

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Frontiers of Information Technology & Electronic Engineering 2017年第10期18卷 1479-1487页

作者： Xue-song CHEN School of Applied Mathematics Guangdong University of TechnologyGuangzhou 510006China

We investigate the use of an approximation method for obtaining near-optimal solutions to a kind of nonlinear continuous-time(CT) system. The approach derived from the Galerkin approximation is used to solve the generalized Hamilton-Jacobi-Bellman(GHJB) equations. The Galerkin approximation with Legendre polynomials(GALP) for GHJB equations has not been applied to nonlinear CT systems. The proposed GALP method solves the GHJB equations in CT systems on some well-defined region of attraction. The integrals that need to be computed are much fewer due to the orthogonal properties of Legendre polynomials, which is a significant advantage of this approach. The stabilization and convergence properties with regard to the iterative variable have been *** examples show that the update control laws converge to the optimal control for nonlinear CT systems.

关键词： Generalized Hamilton-Jacobi-Bellman equation Nonlinear optimal control Galerkin approximation Legendre polynomials

Re-Os Dating of Chalcopyrite from the Lala IOCG Deposit in the Kangdian Copper Belt,China

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Acta Geologica Sinica(English Edition) 2015年第2期89卷 689-690页

作者： song Hao song Shiwei Chengdu University of Technology Institute of Mineral Resources Chinese Academy of Geological Sciences

This study focused on the typical Precambrian copper- iron-gold-uranium deposits in the southwestern margin of the Yangtze block, such as the Lala in Huili, Dahongshan in Xinping, Yinachang in Wuding, and Chahe in Yuanjiang. Through systematically sampling of rocks, mineral and single mineral samples, this study discussed the continental geodynamics, age of magmatic rocks and metallogenic epoch, coupling relationship between polymetallic elements and ore-forming fluid, and the coupling relationship between magma evolution and polymetallic mineralization based on the latest metallogenic theory and modern analytical techniques.

关键词： Re-Os Dating of Chalcopyrite from the Lala IOCG Deposit in the Kangdian Copper Belt,China Os

Preparation and Characterization of the Modified Polyvinylidene Fluoride (PVDF) Hollow Fibre Microfiltration Membrane

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Journal of Materials Science & Technology 2007年第1期23卷 55-60页

作者： Laizhou song Zunju ZHANG Shizhe song Zhiming GAO School of Environment ancl Chemical Engineering Yanshan University Qinhuangdao 066004 China School of Material Science and Engineering Tianjin University Tianjin 300072 China

A novel thermally induced graft polymerization technique was used to modify a polyvinylidene fluoride （PVDF） hollow fibre microfiltration membrane. An artificial neural network （ANN） was applied to optimize the prepared condition of the membrane. The optimized dosing of acrylic acid （AA）, acrylamide （AM）, N, N＇- methylenebisacrylamide （NMBA） and potassium persulphate （KSP） designed by ANN was that AA was 40.63 ml/L; AM acted as 6.25 g/L; NMBA was 1.72 g/L and KSP was 1.5 g/L, respectively. The thermal stability of the PVDF modified hollow fibre membrane （PVDF-PAA） was investigated by thermogravimetric （TG） and differential scanning calorimetry （DSC） analysis. The polycrystallinity of the PVDF-PAA membrane was evaluated by X-ray diffraction （XRD） analysis. The complex formation of the modified membrane was ascertained by Fourier transform infrared spectroscopy （FTIR）. The morphology of the PVDF-PAA membrane was studied by environmental scanning electron microscopy （ESEM）. The surface compositions of the membrane were analyzed by X-ray photoelectron spectroscopy （XPS）. The adsorption capacity of Cu^2＋ ion on the PVDF-PAA hollow fibre membrane was also investigated.

关键词： Microfiltration hollow fibre membrane Graft polymerization modification Acrylic acid Polyvinylidene fluoride Cu^2+ ion

Extraction of palladium(Ⅱ) from hydrochloride solutions with 2-n-octyl-4-isothiazolin-3-one as novel extractant

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Rare Metals 2013年第4期32卷 425-430页

作者： song-Ping Wu School of Chemistry and Chemical Engineering South China University of Technology

Solvent extraction of palladium （Ⅱ） from hydrochloric acid solution with 2-n-octyl-4-isothiazolin-3-one （OIT）/cyclohexane was studied. Effects of different parameters on extraction efficiency were evaluated. 99.96 % and 98.26 % palladium （Ⅱ） could be effectively extracted with 0.018 mol·L^-1 OIT/cyclohexane of 0.1 and 4.0 mol·L^-1 HCl medium, respectively. Nonpolar solvent and low acidity could improve the extracting efficiency, and successfully strip palladium （Ⅱ） from the loaded organic phase was achieved with 0.5 mol·L^-1 （NH2）2CS solution. It was proposed that the extraction of Pd com-plexes from HCl medium proceeded through the ion-association mechanism by slope method, NMR and FF-IR spectra.

关键词： Solvent extraction Palladium 2-n-octyl-4-isothiazolin-3-one OIT Stripping