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A Home-made Simple Set-up for Measurement of Electrochemical Surface Tension Spectrum on a Mercury Drop Electrode

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Chinese Chemical Letters 2006年第4期17卷 493-495页

作者： xiang qin lin liang dong feng Hao ZHANG University of Science and Technology of China Hefei 230026

A setup for recording surface tension curves at a mercury drop during potential scanning is designed based on photo-sensitive detection system. Surface tension spectrum at Hg drop can be recorded by voltam0metdc study. A Yb（Ⅲ）-NO2 catalytic reduction system was used for characterization. The simple, sensitive technique can be expected to provide fresh information on molecular interactions at electrode surfaces.

关键词： Surface tension electrochemistry mercury drop measurement.

Online Condition Monitoring of Gripper Cylinder in TBM Based on EMD Method

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Chinese Journal of Mechanical Engineering 2017年第6期30卷 1325-1337页

作者： lin Li Jian-feng Tao Hai-dong Yu Yi-xiang Huang Cheng-liang Liu State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong University Shanghai 200240 China Shanghai Key Laboratory of Digital Manufacture for Thin-walled Structures Shanghai 200240 China

The gripper cylinder that provides braced force for Tunnel Boring Machine （TBM） might fail due to severe vibration when the TBM excavates in the tunnel. Early fault diagnosis of the gripper cylinder is important for the safety and efficiency of the whole tunneling project. In this paper, an online condition monitoring system based on the Empirical Mode Decomposition （EMD） method is estab- lished for fault diagnosis of the gripper cylinder while TBM is working. Firstly, the lumped mass parameter model of the gripper cylinder is established considering the influence of the variable stiffness at the rock interface, the equivalent stiffness of the oil, the seals, and the copper guide sleeve. The dynamic performance of the gripper cylinder is investigated to provide basis for its health condition evaluation. Then, the EMD method is applied to identify the characteristic frequencies of the gripper cylinder for fault diagnosis and a field test is used to verify the accuracy of the EMD method for detection of the characteristic frequencies. Furthermore, the contact stiff- ness at the interface between the barrel and the rod is calculated with Hertz theory and the relationship between the natural frequency and the stiffness varying with the health condition of the cylinder is simulated based on the dynamic model. The simulation shows that the character- istic frequencies decrease with the increasing clearance between the barrel and the rod, thus the defects could be indicated by monitoring the natural frequency. Finally, a health condition management system of the gripper cylin- der based on the vibration signal and the EMD method is established, which could ensure the safety of TBM.

关键词： Fault diagnosis - Empirical modedecomposition (EMD) Condition Monitoring - Grippercylinder TBM

In situ XAFS Investigation on Zincblende ZnS up to 31.7 GPa

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Chinese Physics Letters 2013年第4期30卷 129-132页

作者： YANG Jun ZHU feng ZHANG Qian WU Ye WU xiang qin Shan dong Jun-Cai CHEN dong-liang Key Laboratory of Orogenic Belts and Crustal Evolution(Ministry of Education and School of Earth and Space SciencesPeking UniversityBeijing 100871 Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of ScienceBeijing 100049

In situ high-pressure x-ray absorption fine structure(EXAFS)measurements on the Zn K-edge in zincblende ZnS are performed up to 31.7 GPa at room temperature using a synchrotron radiation x-ray re-focused by a polycapillary half-lens in the classic energy-scanning transmission *** present XAFS data illustrate that ZnS undergoes a phase transition from zincblende F43m to rocksalt Fm3m at 16.9 GPa,accompanied by the increase of the first shell coordination number of the absorption zinc atoms and the unit-cell volume collapse of~14%.The isothermal equation of state of the F43m ZnS is well presented by the third-order Birch–Murnaghan equation of state with V0=158.6±0.8?3,B0=87±5 GPa and B0'=4(fixed).The high-pressure behavior of ZnS from the XAFS spectra is consistent with the previous high-pressure XRD *** addition,the present experimental method demonstrates that the large divergent x-ray micro-beam induced by a polycapillary half-lens can suppress effectively the glitches from single crystal diamond anvil and improve significantly the quality of the XAFS data,which will shed light on the high-pressure XAFS applications.

关键词： XAFS absorption capillary

High thermal conductivity and remarkable damping composite gels as thermal interface materials for heat dissipation of chip

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Chip 2022年第2期1卷 27-34页

作者： Sheng-Chang Ding Jian-feng Fan dong-Yi He lin-feng Cai xiang-liang Zeng lin-lin Ren Guo-Ping Du Xiao-liang Zeng Rong Sun Shenzhen Institute of Advanced Electronic Materials Shenzhen Institute of Ad-vanced TechnologyChinese Academy of SciencesShenzhen518055China School of Physics and Materials Science Nanchang UniversityNanchang 330031China

The emerging applications of composite gels as thermal interface ma-terials(TIMs)for chip heat dissipation in intelligent vehicle and wear-able devices require high thermal conductivity and remarkable damp-ing ***,thermal conductivity and damping proper-ties are usually correlated and coupled each ***,inspired by Maxwell theory and adhesion mechanism of gecko’s setae,we present a strategy to fabricate polydimethylsiloxane-based composite gels in-tegrating high thermal conductivity and remarkable damping prop-erties over a broad frequency and temperature *** multiple relaxation modes of dangling chains and the dynamic interaction be-tween the dangling chains and aluminum fillers can efficiently dis-sipate the vibration energy,endowing the composite gels with ultra-high damping property(tanδ>0.3)over a broad frequency(0.01-100 Hz)and temperature range(-50-150°C),which exceeds typi-cal state-of-the-art damping *** dangling chains also com-fort to the interfaces between polymer matrix and aluminum via van der Waals interaction,resulting in high thermal conductivity(4.72±0.04 W m-1 K-1).Using the polydimethylsiloxane-based composite gel as TIMs,we demonstrate effective heat dissipation in chip oper-ating under vigorous *** believe that our strategy could be applied to a wide range of composite gels and lead to the devel-opment of high-performance composite gels as TIMs for chip heat dissipation.

关键词： Thermal interface materials Composite gels Damping Ther-mal conductivity Dangling chains

Community structure and species diversity dynamics of a subtropical evergreen broad-leaved forest in China:2005 to 2020

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Plant Diversity 2024年第1期46卷 70-77页

作者： Shi-Guang Wei lin Li Kun-dong Bai Zhi-feng Wen Jing-Gang Zhou qin lin Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection(Guangxi Normal University) Ministry of EducationGuilin 541004GuangxiChina School of Life&Environmental Sciences Guilin University of Electronic TechnologyGuilin 541004GuangxiChina Guangxi Key Laboratory of Landscape Resources Conservation and Sustainable Utilization in Lijiang River Basin Guilin 541004GuangxiChina Key Laboratory of Vegetation Restoration and Management of South China Botanical Garden of Degraded Ecosystems Chinese Academy of SciencesGuangzhou 510650GuangdongChina Center of Plant Ecology Core Botanical GardensChinese Academy of SciencesGuangzhou 510650GuangdongChina

Here,we characterize the temporal and spatial dynamics of forest community structure and species diversity in a subtropical evergreen broad-leaved forest in *** found that community structure in this forest changed over a 15-year ***,renewal and death of common species was large,with the renewal of individuals mainly concentrated within a few populations,especially those of Aidia canthioides and Cryptocarya *** numbers of individual deaths for common species were concentrated in the small and mid-diameter *** spatial distribution of community species diversity fluctuated in each monitoring period,showing a more dispersed diversity after the 15-year study period,and the coefficient of variation on quadrats *** 2010,the death and renewal of the community and the spatial variation of species diversity were different compared to other survey *** weather may have affected species regeneration and community stability in our subtropical monsoon evergreen broad-leaved *** findings suggest that strengthening the monitoring and management of the forest community will help better understand the long-and short-term causes of dynamic fluctuations of community structure and species diversity,and reveal the factors that drive changes in community structure.

关键词： Community structure Death and renewal dynamics Species diversity dynamics South subtropical forest

Photodamage to Pigment in the Photosystem Ⅱ Reaction Center D1/D2/Cytochrome b559 Complex

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Journal of Integrative Plant Biology 2006年第7期48卷 800-806页

作者： Shuang Liu feng-qin dong Chong-qin Tang Ting-Yun Kuang liang-Bi Li Yu-Long Liu Institute of Botany the Chinese Academy of Sciences Beijing 100093 China Institute of Physics the Chinese Academy of Sciences Beijing 100080 China

Strong light （800μmol photons/m^2 per s）-induced bleaching of the pigment in the isolated photosystem Ⅱ reaction center （PSII RC） under aerobic conditions （in the absence of electron donors or acceptors） was studied using high-pressure liquid chromatography （HPLC）, absorption spectra, 77K fluorescence spectra and resonance Raman spectra. Changes in pigment composition of the PSII RC as determined by HPLC after light treatment were as follows： with Increasing illumination time chlorophyll （Chl） a and β-carotene （β-car） content decreased. However, decreases in pheophytin （Pheo） could not be observed because of the mixture of the Pheo formed by degraded chlorophyll possibly. On the basis of absorption spectra, it was determined that, with a short time of illuminatlon, the initial bleaching occurred maximally at 680 nm but that with Increasing Illumination time there was a blue shift to 678 nm. It was suggested that P680 was destroyed Initially, followed by the accessory chlorophyll. The activity of P680 was almost lost after 10 mln light treatment. Moreover, the bleaching of Pheo and β-car was observed at the beginning of illumination. After Illumination, the fluorescence emission Intensity changed and the fluorescence maximum blue shifted, showing that energy transfer was disturbed. Resonance Raman spectra of the PSII RC excited at 488.0 and 514.5 nm showed four main bands, peaking at 1 527 cm^-1 （υ101）, 1 159 cm^-1 （υ2）, 1 006 cm^-1 （υ3）, 966 cm^-1 （υ4） for 488.0 nm excitation and 1 525 cm^-1 （υ1）, 1 159 cm^-1 （υ2）, 1 007 cm^-1 （υ3）, 968 cm^-1 （υ4） for 514.5 nm excitation. It was confirmed that two spectroscopically different β-car molecules exist In the PSII RC. After light treatment for 20 mln, band positions and bandwidths were unchanged. This indicates that carotenoid configuration Is not the parameter that regulates photoprotectlon in the PSII RC.

关键词： high-pressure liquid chromatography (HPLC) photodamage photosystem Ⅱ reaction center (PSII RC) resonance Raman spectroscopy

Influence of bias voltage on structure,mechanical and corrosion properties of reactively sputtered nanocrystalline TiN films

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Journal of Iron and Steel Research International 2017年第12期24卷 1223-1230页

作者： Chun-lin He Jin-lin Zhang Guo-feng Ma Zhao-fu Du Jian-ming Wang dong-liang Zhao Liaoning Provincial Key Laboratory of Advanced Materials Shenyang UniversityShenyang 110044LiaoningChina Research Institute of Functional Materials Central Iron&Steel Research InstituteBeijing 100081China

Nanocrystalline TiN films were prepared by DC reactive magnetron *** influence of substrate biases on structure,mechanical and corrosion properties of the deposited films was studied using X-ray diffraction,field emission scanning electron microscopy,nanoindentation and electrochemical *** deposited films have a columnar structure,and their preferential orientation strongly depends on bias *** preferential orientations change from（200）plane at low bias to（111）plane at moderate bias and then to（220）plane at relatively high *** H,elastic modulus E,H/E＊and H3/E＊2 ratios,and corrosion resistance of the deposited films increase first and then decrease with the increase in bias *** the best values appear at bias of-120 V,attributing to the film with a fine,compact and less defective *** demonstrates that there is a close relation among microstructure,mechanical and corrosion properties of the TiN films,and the film with the best mechanical property can also provide the most effective corrosion protection.

关键词： TiN film Nanocrystalline Bias voltage Microstructure Mechanical property Corrosion resistance

Genetic Analysis on Characteristics to Measure Drought Resistance Using dongxiang Wild Rice(Oryza rufupogon Griff.) and Its Derived Backcross Inbred lines Population at Seedling Stage

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Agricultural Sciences in China 2011年第11期10卷 1653-1664页

作者： HU Biao-lin FU Xue-qin ZHANG Tao WAN Yong LI Xia HUANG Ytm-hong DAI liang-fang LUO xiang-dong XIE Jian-kun Rice Research Institute Jiangxi Academy of Agricultural Sciences Nanchang 330200 P.R.China College of Life Sciences Jiangxi Normal University Nanchang 330022 P.R. China

Drought stress is one of the major constraints to rice （Oryza sativa L.） production and yield stability especially in rainfed ecosystems and is getting worse as the climate changes worldwide. dongxiang wild rice （DXWR） Oryza rufipogon Griff., contains drought resistant gene. Improving drought resistance of cultivars is crucial to increase and stabilize rice grain yield via transferring resistant gene from species related to rice. In this paper, four upland rice, sixty backcross inbred lines （BILs） derived from BC1F5 of R974//DXWR/R974, and their parents were employed to evaluate drought-resistance at seedling stage in the greenhouse. Nine traits were recorded for assessment of drought resistance, including maximum root length （MRL）, number of roots （NR）, shoot length （SL）, dry root weight （DRW）, fresh root weight （FRW）, root relative water content （RRWC）, leaf relative water content （LRWC）, level for rolling leaf （LRL）, and seedling survivability under repeat drought （SSRD）. Using more than 88% of accumulative contribution resulted from the principal component analysis （PCA）, the nine traits were classified into five independent principal components and the line 1949 showed the highest resistance. Analysis on the stepwise regression equation and correlation demonstrated that MRL, RN, FRW, and RRWC significantly influenced the drought resistance, thus could be used as comprehensive index for drought resistance at the seedling stage. Using the major gene plus polygene mixed inheritance model of quantitative traits, the inheritance of drought-resistance of BIL population at seedling stage was mostly controlled by two independent genes plus polygene. As a result, the DXWR could be precious resources for genetic improvement of drought resistance in cultivated rice.

关键词： dongxiang wild rice (DXWR) drought resistance principal component analysis (PCA) drought comprehensiveindex seedling stage

Shear wave elastography results correlate with liver fibrosis histology and liver function reserve

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World Journal of Gastroenterology 2016年第17期22卷 4338-4344页

作者： Yan-Hong feng xiang-dong Hu lin Zhai Ji-Bin Liu Lan-Yan Qiu Yuan Zu Si liang Yu Gui lin-Xue Qian Department of Ultrasound Medicine Beijing Friendship Hospital Capital Medical University Division of Diagnostic Ultrasound Department of Radiology Thomas Jefferson University

AIM: To evaluate the correlation of shear wave elastography (SWE) results with liver fibrosis histology and quantitative function reserve. METHODS: Weekly subcutaneous injection of 60% carbon tetrachloride (1.5 mL/kg) was given to 12 canines for 24 wk to induce experimental liver fibrosis, with olive oil given to 2 control canines. At 24 wk, liver condition was evaluated using clinical biochemistry assays, SWE imaging, lidocaine metabolite monoethylglycine-xylidide (MEGX) test, and histologic fibrosis grading. Clinical biochemistry assays were performed at the institutional central laboratory for routine liver function evaluation. Liver stiffness was measured in triplicate from three different intercostal spaces and expressed as mean liver stiffness modulus (LSM). Plasma concentrations of lidocaine and its metabolite MEGX were determined using high-performance liquid chromatography repeated in duplicate. Liver biopsy samples were fixed in 10% formaldehyde, and liver fibrosis was graded using the modified histological activity index Knodell score (F0-F4). Correlations among histologic grading, LSM, and MEGX measures were analyzed with the Pearson linear correlation coefficient. RESULTS: At 24 wk liver fibrosis histologic grading was as follows: F0, n = 2 (control); F1, n = 0; F2, n = 3; F3, n = 7; and F4, n = 2. SWE LSM was positively correlated with histologic grading (r = 0.835, P < 0.001). Specifically, the F4 group had a significantly higher elastic modulus than the F3, F2, and F0 groups (P = 0.002, P = 0.003, and P = 0.006, respectively), and the F3 group also had a significantly higher modulus than the control F0 group (P = 0.039). LSM was negatively associated with plasma MEGX concentrations at 30 min (r = -0.642; P = 0.013) and 60 min (r = -0.651; P = 0.012), time to 1/2 of the maximum concentration (r = -0.538; P = 0.047), and the area under the curve (r = -0.636; P = 0.014). Multiple comparisons showed identical differences in these three measures: signific

关键词： Liver fibrosis Histologic grading Shear wave elastography Monoethylglycinexylidide test Experimental study