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Eco-toxicity of petroleum hydrocarbon contaminated soil

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Journal of Environmental Sciences 2011年第5期23卷 845-851页

作者： Jingchun Tang Min Wang fei Wang qing Sun Qixing Zhou College of Environmental Science and Engineering Nankai University/Key Laboratory of Pollution Processes and Environmental Criteria Ministry of Education Tianjin 300071 China. E-mail: tangjch@***

Total petroleum hydrocarbons （TPH） contaminated soil samples were collected from Shengli Oilfield of China. Toxicity analysis was carried out based on earthworm acute toxicity, plant growth experiment and luminescent bacteria test. The soil was contaminated by- petroleum hydrogcarbons with TPH concentration of 10.57%. With lethal and sub-lethal rate as endpoint, earthworm test showed that the LD50 （lethal dose 50%） values in 4 and 7 days were 1.45% and 1.37% respectively, and the inhibition rate of earthworm body weight increased with higher oil concentration. TPH pollution in the soil inhibited seed germination in both wheat and maize experiment when the concentration of petroleum was higher than 0.1%. The EC50 （effective concentration 50%） for germination is 3.04% and 2.86% in maize and wheat, respectively. While lower value of EC50 for root elongation was to be 1.11% and 1.64% in maize and wheat, respectively, suggesting higher sensitivity of root elongation on petroleum contamination in the soil. The EC50 value in luminescent bacteria test was 0.47% for petroleum in the contaminated soil. From the experiment result, it was concluded that TPH content of 1.5% is considered to be a critical value for plant growth and living of earthworm and 0.5% will affect the activity of luminescent bacteria.

关键词： toxicity total petroleum hydrocarbon soil earthworm contamination

Dynamics and formation of vortices collapsed from ring dark solitons in a two-dimensional spin–orbit coupled Bose–Einstein condensate

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Frontiers of physics 2022年第4期17卷 185-193页

作者： Peng-Hong Lu Xiao-fei Zhang Chao-qing Dai College of Optical Mechanical and Electrical EngineeringZhejiang A&F UniversityLin’an 311300China Department of Physics Shaanxi University of Science and TechnologyXi’an 710021China

We consider the dynamics and formation of vortices from ring dark solitons in a two-dimensional Bose–Einstein condensate with the Rashba spin–orbit coupling based on the time-dependent coupled Gross–Pitaevskii *** with previous results,the system exhibits complex dynamical behaviors in the presence of the spin–orbit *** the modulation of the spin–orbit coupling,not only the lifetime of ring dark solitons is greatly prolonged,but also their attenuation kinetics is significantly *** two shallow ring dark solitons with the equal strength of the spin–orbit coupling,the radius of ring dark solitons increases to a maximum value over time and then shrinks into a minimum *** to the effect of the snake instability,ring dark solitons split into a series of ring-like clusters of vortex pairs,which perform complex *** indicates that the system is strongly dependent on the presence of the spin–orbit ***,the effect of different initial modulation depths on the dynamics of ring dark solitons is investigated.

关键词： Bose–Einstein condensate Rashba spin–orbit coupling ring dark solitons vortex pairs

Least Squares Evaluations for Form and Profile Errors of Ellipse Using Coordinate Data

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Chinese Journal of Mechanical Engineering 2016年第5期29卷 1020-1028页

作者： LIU fei XU Guanghua LIANG Lin ZHANG qing LIU Dan School of Mechanical Engineering Xi'an Jiaotong University State Key Laboratory for Manufacturing Systems Engineering Xi'an Jiaotong University Key Laboratory of Education Ministry for Modern Design and Rotor-Bearing System Xi'an Jiaotong University

To improve the measurement and evaluation of form error of an elliptic section, an evaluation method based on least squares fitting is investigated to analyze the form and profile errors of an ellipse using coordinate data. Two error indicators for defining ellipticity are discussed, namely the form error and the profile error, and the difference between both is considered as the main parameter for evaluating machining quality of surface and profile. Because the form error and the profile error rely on different evaluation benchmarks, the major axis and the foci rather than the centre of an ellipse are used as the evaluation benchmarks and can accurately evaluate a tolerance range with the separated form error and profile error of workpiece. Additionally, an evaluation program based on the LS model is developed to extract the form error and the profile error of the elliptic section, which is well suited for separating the two errors by a standard program. Finally, the evaluation method about the form and profile errors of the ellipse is applied to the measurement of skirt line of the piston, and results indicate the effectiveness of the evaluation. This approach provides the new evaluation indicators for the measurement of form and profile errors of ellipse, which is found to have better accuracy and can thus be used to solve the difficult of the measurement and evaluation of the piston in industrial production.

关键词： ellipse form Error profile error least squares method piston

Effect of Frequency on Degradation in BOPP Films Under Repetitively Pulsed Voltage

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 1280-1290页

作者： Chuansheng Zhang Yu Feng fei kong Bangdou Huang Cheng Zhang Tao Shao Beijing International S&T Cooperation Base for Plasma Science and Energy Conversion Institute of Electrical EngineeringChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Operating conditions of film capacitors are complex,and the problem of film insulation failure caused by repetitively pulsed voltage is becoming ever *** of the film under repetitively pulsed voltage cannot be accurately evaluated by the average breakdown electric *** this paper,the effects of pulsed electric field and pulse repetition frequency on the breakdown in biaxially oriented polypropylene(BOPP)films are *** phases of BOPP degradation are proposed based on the voltage amplitude,i.e.,maintenance(M),decline(D),and near-zero(N).Evolution of the BOPP film from degradation to breakdown at different frequencies is ***,transition of discharge mode and elemental composition of the film are *** results show continuous heat generation under repetitive microsecond pulses is the dominant factor for degradation of BOPP *** number of applied pulses and the repetitive stressing time decrease exponentially with increase of *** research can be contributed to the safe and reliable operation of capacitors.

关键词： Aging breakdown film capacitor polypropylene repetitive pulse

Half-sandwich 1,3-Di-t-butylcyclopentadienyl Rhodium Complexes Containing Sulfido Ligands

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应用化学 2001年第5期18卷 322-329页

作者： kong qing-An JIN Guo-Xin Changchun Institute of Applied Chemistry Chinese Academy of SciencesChangchun 130022

Treatment of 1,3-di- t -butylcyclopentadiene with rhodium trichloride in EtOH leads to the formation of binuclear half-sandwich complex [Cp t RhCl( μ -Cl)] 2 (1) (Cp t = η 5- t Bu 2C 5H 3) which reacts with trimethylphosphine to give Cp t Rh(PMe 3)Cl 2(2) in high yield. 2 reacts with ammonium polysulfide, (NH 4) 2S x to give cyclooligosulfido half-sandwich complexes Cp t Rh(PMe 3)(S n )( n =4(4a),6(4b)). Desulfurization of 4b by excess PPh 3 results in cyclotetrasulfido product 4a, while 4a takes up sulfur from polysulfide to convert cyclohexasulfido product 4b. The reaction of 2 with Et 4NI gives diiodide complex 3 which is determined by single crystal X-ray crystallographic analysis.

关键词：铑配合物脱硫金属环齐聚硫化物 X射线晶体结构

A new calibration model for pointing a radio telescope that considers nonlinear errors in the azimuth axis

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Research in Astronomy and Astrophysics 2014年第6期14卷 733-740页

作者： De-qing kong Song-Gen Wang Jin-qing Wang Min Wang Hong-Bo Zhang National Astronomical Observatories Chinese Academy of Sciences College of Mechanical Engineering Hangzhou Dianzi University Shanghai Astronomical Observatory Chinese Academy of Sciences Yunnan Observatories Chinese Academy of Sciences

A new calibration model of a radio telescope that includes pointing error is presented, which considers nonlinear errors in the azimuth axis. For a large radio telescope, in particular for a telescope with a turntable, it is difficult to correct pointing errors using a traditional linear calibration model, because errors produced by the wheel-on-rail or center bearing structures are generally nonlinear. Fourier expansion is made for the oblique error and parameters describing the inclination direction along the azimuth axis based on the linear calibration model, and a new calibration model for pointing is derived. The new pointing model is applied to the 40 m radio telescope administered by Yunnan Observatories, which is a telescope that uses a turntable. The results show that this model can significantly reduce the residual systematic errors due to nonlinearity in the azimuth axis compared with the linear model.

关键词： telescopes - antennas - pointing models

Insight into relationship between composition,thickness and electrochemistry behavior of oxide film formed on TA15under different potentials in 0.5 mol·L^(-1)H_(2)SO_(4)

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Rare Metals 2023年第5期42卷 1760-1772页

作者： fei-fei Huang Yi Qin qing-Rui Wang Hiroaki Yoshida Lei Wen Hai Chang Ying Jin National Center for Materials Service Safety University of Science and Technology BeijingBeijing100083China Innovation Group of Marine Engineering Materials and Corrosion Control Southern Marine Science and Engineering Guangdong LaboratoryZhuhai519080China Department of Physical Science Hiroshima UniversityHigashi-Hiroshima739-8526Japan

The oxide film formed on TA15 alloy in0.5 mol·L^(-1)H_(2)SO_(4)at different applied potentials is investigated by evaluating the film formation current density,film thickness,surface film composition,valence state,and the electrochemical *** relative quantitative spectral analysis revealed by X-ray photoelectron spectroscopy(XPS)and X-ray absorption spectra(XAS)shows that the increasing applied potential promotes the formation of thick and high-valence state *** contrasting with XAS of the reference titanium oxides,it is found that TiO_(2)within the oxide film changes from anatase type to rutile type with the potential increases to 2.00 *** oxide film formed at passive region has better protection performance,and with the increase of applied potential,the corrosion resistance of passive film increases,whereas the ND(donor density)values obtained from the Mott-Schottky(MS)results decrease with the increasing applied potential,indicating a better uniformity and protective effect of the oxide *** on above facts,the model of the oxide films formed on TA15 at different applied potentials in passive region and dissolve region is ***,the existence forms of all the TA15alloying elements under the most corrosion resistant condition are confirmed.

关键词： TA15 Electrochemical passivation Corrosion behavior Surface compositions and structures

Identification of peanut oil origins based on Raman spectroscopy combined with multivariate data analysis methods

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Journal of Integrative Agriculture 2022年第9期21卷 2777-2785页

作者： ZHU Peng-fei YANG qing-li ZHAO Hai-yan College of Food Science and Engineering Qingdao Agricultural UniversityQingdao 26619P.R.China

This study aimed to use Raman spectroscopy to identify the producing areas of peanut oil and build a robust discriminant model to further screen out the characteristic spectra closely related to the origin. Raman spectra of 159 peanut oil samples from different provinces and different cities of the same province were collected. The obtained data were analyzed by stepwise linear discriminant analysis(SLDA), k-nearest neighbor analysis(k-NN),support vector machine(SVM) and multi-way analysis of variance. The results showed that the overall recognition rate of samples based on full spectra was higher than 90%. The producing origin, variety and their interaction influenced Raman spectra of peanut oil significantly, and 1 400–1 500 cmand 1 600– 1 700 cmwere selected as the characteristic spectra of origin and less affected by variety. The best classification model established by SLDA combined with characteristic spectra could rapidly and accurately identify peanut oil’s origin.

关键词： Raman spectroscopy peanut oil large-scale district small-scale district variety chemometrics

Synthesis, crystal structure and thermal analysis of a new stilbazolium salt crystal

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Frontiers of Materials Science 2015年第2期9卷 147-150页

作者： Bing TENG Weijin kong Ke FENG fei YOU Lifeng CAO Degao ZHONG Lun HAO qing SUN Sander van SMAALEN Wenhui GONG College of Physics Qingdao University Qingdao 266071 China Key Laboratory of Photonics Materials and Technology in Universi~iesof Shand'ongl qingdao 266071 China Laboratory of Crystallography Universityof Bayreuth D-95440 BayreuihGermany

A new organic crystal of 4-N, N-dimethylamino-4＇-N＇-methyl-stilbazolium benzene sulfonate （DASBS） was synthesized and characterized for the first time. It is a derivative of 4-N, N-dimethylamino-4＇-N＇-methyl-stilbazolium tosylate （DAST） with the benzene sulfonate replacing p-toluenesulfonate. Single crystal XRD demonstrated that the crystal structure of DASBS. H20 was triclinic. The thermal analysis of this new crystal was also conducted, and the melting point was obtained to be 232℃.

关键词： organic crystal crystal growth single crystal X-ray diffraction thermalanalysis