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Spatial-temporal evolution of vegetation evapotranspiration in Hebei Province,China

Journal of Integrative Agriculture 2018年第9期17卷 2107-2117页

作者： WANG Qian-feng TANG jia ZENG Jing-yu QU Yan-ping ZHANG Qing shui Wei WANG Wu-lin YI Lin LENG Song Fujian Provincial Key Laboratory of Remote Sensing of Soil Erosion and Disaster Protection/College of Environment and Resources Fuzhou UniversityFuzhou 350116P.R.China Research Center on Flood and Drought Disaster Reduction China Institute of Water Resources and Hydropower Reseat'chBeijing 100038P.R.China Key Laboratory of Digital Earth Science Institute of Remote Sensing and Digital EarthChinese Academy of ScienceBeijing 100094P.R.China Geospatial Information Center Shenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhen 518055P.R.China Climate Change Cluster University of Technology SydneyNew South Wales 2007Australia

Evapotranspiration （ET） is the sum of soil or water body evaporation and plant transpiration from the earth surface and ocean to the atmosphere, and thus plays a significant role in regulating carbon and water resource cycles. The time-series data set from the remote sensing MOLDS product （MOD16） was used to study the spatial-temporal evolution of vegetation evapotranspiration in salinized areas during 2000-2014 by analyzing the variability, spatial patterns and Mann-Kendall （MK） nonparametric trends for the time series. The results indicate that inter-annual and intra-annual variations of ET across various vegetated areas show seasonal changes, with the abnormal months identified. The Cultivated land displays a greater degree of spatial heterogeneity and the spatial pattern of ET in the area covered by broadleaved deciduous forests corresponds to a higher ET rate and increased water consumption. Awidespread decline of ET is observed only in cultivated areas. However, agricultural cultivation doesn＇t worsen water shortage and soil salinization problems in the region, and water shortage problems are worsening for other vegetated areas. This research provides a basis of reference for the reasonable allocation of water resources and restructuring of vegetation patterns in salinized areas.

关键词： evapotranspiration Hebei Province MODIS spatial pattern vegetation spatial-temporal evolution

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Preparation and Kinetics of a Novel Glutathione Peroxidase Mimic——Selenium-modified Hyaluronic Acid

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Chemical Research in Chinese Universities 2007年第3期23卷 325-328页

作者： CHEN jia HONG shui-sheng AN Yang jiaNG Guang-zhi ZHANG Bo-xun FANG Xiang-yang LIU Lan-ying TENG Li-rong College of life Science Jilin University Changchun 130021 P. R. China

A selenium-modified hyaluronic acid（HA） compound（SeHA） was synthesized as a mimic of glutathione peroxidase（GPX）. IR and NMR spectra of SeHA predict that the --CH2OH group of the N-acetyl-D-glucosamine in HA was modified by group --Sell. There are averagely 152 --Sell groups in one SeHA molecule. The GPX activities are 103.88, 32. 15 and 152. 71 U/μmol, respectively, when the substrates were H2O2, BuOOH and CuOOH. Ping-pong mechanism was observed in the steady-state kinetic studies of the reactive oxygen species（ROS） consuming reaction. Result of reactions of SeHA with free radical capturer 2,6-di-tert-butyl-4-methylphenol（BHT） shows that the catalysis is based on a non-free radical-mechanism and the SeHA can not be inhibited by iodoacetate, an enzyme inhibitor.

关键词： Selenium-modified hyaluronic acid GPX Preparation Kinetics

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Rate-dependent constitutive model of poly(ethylene terephthalate) for dynamic analysis

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第10期11卷 811-816页

作者： Qiang LI Shu-lian LIU shui-ying ZHENG Institute of Chemical Machinery Zhejiang University Hangzhou 310027 China Department of Electro-Mechanical Engineering Zhejiang University of Science and Technology Hangzhou 310023 China

Uniaxial tensile testing at strain rates ranging from 10-3 to 10-1 s-1 was carried out to study the rate-dependent me-chanical behavior for poly(ethylene terephthalate) (PET) used in the packaging industry. The experimental results show that a rate-dependent plastic behavior exists for PET material. The value of the yield strength was found to increase with the increasing strain rate. A new constitutive model based on the improved Cowper-Symonds rate-dependent constitutive model is proposed to describe the mechanical behavior of PET material in the strain rate ranging from 10-3 to 10-1 s-1, providing more accurate material data for the subsequent simulation analysis of drop test and dynamic buckling. The predictions obtained using the proposed model are compared with experimental results of the improved Cowper-Symonds model. The simulating results of the proposed model agree well with the experimental data. For a low strain rate, the predictions of this model are more precise than those obtained using the improved Cowper-Symonds model. This confirms that the new constitutive model is suitable for describing the me-chanical behavior of PET material at a low strain rate and modeling impact problem.

关键词： Rate-dependent Tensile testing Constitutive model Strain rate Poly(ethylene terephthalate) (PET)

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Modified unscented Kalman filter using modified filter gain and variance scale factor for highly maneuvering target tracking

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Journal of Systems Engineering and Electronics 2014年第3期25卷 380-385页

作者： Changyun Liu Penglang shui Gang Wei Song Li National Laboratory of Radar Signal Processing Xidian University College of Air and Missile Defense Air Force Engineering University

To improve the low tracking precision caused by lagged filter gain or imprecise state noise when the target highly maneuvers, a modified unscented Kalman filter algorithm based on the improved filter gain and adaptive scale factor of state noise is presented. In every filter process, the estimated scale factor is used to update the state noise covariance Qk, and the improved filter gain is obtained in the filter process of unscented Kalman filter （UKF） via predicted variance Pk｜k-1, which is similar to the standard Kalman filter. Simulation results show that the proposed algorithm provides better accuracy and ability to adapt to the highly maneuvering target compared with the standard UKF.

关键词： unscented Kalman filter (UKF) target tracking filter gain maneuvering target nonlinearity modified unscented Kalman filter (MUKF).

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Laser-enhanced thermal effect of moderate intensity focused ultrasound on bio-tissues

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Science China(Physics,Mechanics & Astronomy) 2017年第9期60卷 28-36页

作者： JinYu Zhao ShuYi Zhang XiuJi shui Li Fan Laboratory of Modern Acoustics Institute of Acoustics Collaborative Innovation Center of Advanced Microstructures Nanjing University

For avoiding extra-damage to healthy tissues surrounding the focal point during high intensity focused ultrasound(HIFU) treatment in medical therapy, to reduce the ultrasonic intensity outside the focal point is expected. Thus, the heating processes induced by moderate intensity focused ultrasound(MIFU) and enhanced by combined irradiation of laser pulses for bio-tissues are studied in details. For fresh bio-tissues, the enhanced thermal effects by pulsed laser combined with MIFU irradiation are observed experimentally. To explore the mechanisms of these effects, several tissue-mimicking materials composed of agar mixed with graphite powders are prepared and studied for comparison, but the laser-enhanced thermal effects in these mimicking materials are much less than that in the fresh bio-tissues. Therefore, it is suggested that the laser-enhanced thermal effects may be mainly attributed to bio-activities and related photo-bio-chemical effects of fresh tissues.

关键词： bio-tissue focused ultrasound laser pulse irradiation thermal effect

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Comparing results of cultured and uncultured biological methods used in biological phosphorus removal

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Journal of Environmental Sciences 2007年第11期19卷 1373-1379页

作者： LIU Ya-nan XUE Gang YU shui-li School of Environmental Science and Engineering Dong Hua University Shanghai 201620 China School of Municipal and Environmental Engineering Harbin Institute of Technology Harbin 150090 China

Increasing attention has been paid to phosphate-accumulating organisms （PAOs） for their important role in biological phosphorus removal. In this study, microbial communities of PAOs cultivated under different carbon sources （sewage, glucose, and sodium acetate） were investigated and compared through culture-dependent and culture-independent methods, respectively. The results obtained using denaturing gradient gel electrophoresis （DGGE） of polymerase chain reaction-amplified 16S rDNA fragments revealed that the diversity of bacteria in a sewage-fed reactor （1#） was much higher than in a glucose-fed one （2#） and a sodium acetate-fed one （3#）; there were common PAOs in three reactors fed by different carbon sources. Five strains were separated from three systems by using a phosphaterich medium; they were from common bacteria isolated and three isolates could not be found in DGGE profile at all. Two isolates had good phosphorus removal ability. When the microbial diversity was studied, the molecular biological method was better than the culture-dependent one. When phosphorus removal characteristics were investigated, culture-dependent approach was more effective. Thus a combination of two methods is necessary to have a comprehensive view of PAOs.

关键词： phosphate-accumulating organisms (PAOs) denaturing gradient gel electrophoresis (DGGE) biological phosphorus removal culture-dependent approach culture-independent approach

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Emerging roles and therapeutic potentials of sphingolipids in pathophysiology:emphasis on fatty acyl heterogeneity

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Journal of Genetics and Genomics 2024年第3期51卷 268-278页

作者： Jinming Mu Sin Man Lam Guanghou shui State Key Laboratory of Molecular Developmental Biology Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100101China Lipidall Technologies Company Limited ChangzhouJiangsu 213000China

Sphingolipids not only exert structural roles in cellular membranes,but also act as signaling molecules in various physiological and pathological processes.A myriad of studies have shown that abnormal levels of sphingolipids and their metabolic enzymes are associated with a variety of human ***,blood sphingolipids can also be used as biomarkers for disease *** review summarizes the biosynthesis,metabolism,and pathological roles of sphingolipids,with emphasis on the biosynthesis of ceramide,the precursor for the biosynthesis of complex sphingolipids with different fatty acyl *** possibility of using sphingolipids for disease prediction,diagnosis,and treatment is also *** endogenous ceramides and complex sphingolipids along with their specific fatty acyl chain to promote future drug development will also be discussed.

关键词： Sphingolipids Ceramide Therapeutic targets Microdomain Biomarker

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Influence of rolling temperature on the interfaces and mechanical performance of graphene-reinforced aluminum-matrix composites

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International Journal of Minerals,Metallurgy and Materials 2019年第6期26卷 752-759页

作者： Chen-yang Huang shui-ping Hu Kai Chen Institute of Engineering Technology University of Science and Technology BeijingBeijing 100083China School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China

To study the influence of rolling on the interfaces and mechanical performance of graphene-reinforced Al-matrix composites,a rolling method was used to process *** scanning electron microscopy(SEM),transmission electron microscopy(TEM),X-ray diffraction(XRD),Raman spectroscopy,and tensile testing,this study analyzed the micromorphology,interfaces,and mechanical performance of the composites before and after *** experimental results demonstrates that the composites after hot rolling has uniform structures with strong interfacial *** an increase in rolling temperature,the tensile strength and elastic modulus of the composites gradually ***,when the rolling temperature is higher than 500°C,granular and rod-like Al4C3 phases are observed at the interfaces and the mechanical performance of the composites is *** the rolling temperature is 480°C,the composites show the optimal comprehensive mechanical performance,with a tensile strength and elastic modulus of 403.3 MPa and 77.6 GPa,respectively,which represent increases of 31.6%and 36.9%,respectively,compared with the corresponding values prior to rolling.

关键词： rolling graphene composite interface mechanical performance

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A multi-screen collaboration-based low-cost portable dry-lab simulator for basic laparoscopic skills training: A technical note

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Laparoscopic, Endoscopic and Robotic Surgery 2022年第2期5卷 71-74页

作者： Yifan Chang Chenqi Tang Xianqi shui Yamei Zhou Xiaoyu jiang jia Liu Yu Sun Department of Urology Changhai HospitalNaval Medical UniversityShanghai 200433China Department of Clinical Education-Surgery and Battlefield Surgery Changhai HospitalNaval Medical UniversityShanghai 200433China Department of Burn Surgery Changhai HospitalNaval Medical UniversityShanghai 200433China

Laparoscopic skills training has always been crucial for novice surgeons. Readily accessible equipment, aswell as structured training curriculum should be provided to guarantee adequate practice hours and skillproficiency. Dry-lab training is typically adopted before animal model surgery, usually comprising ofpurpose-built bulky simulators that is neither accessible nor portable. In this technical note, we designed ahome-made simulator, using two 4 L water jugs as operating space that are communicated inside, plus anobservation hole taped in between to mimic the triangular working space of laparoscopic surgery. Imagingwas achieved via smartphone camera, which was wirelessly connected to a laptop and a projector for realtime display on multiple screens, using built-in multi-screen collaboration software. A self-regulated andproficiency-based training curriculum was adopted. This dry-lab simulator is low-cost, highly portable andeasily replicable for basic laparoscopic skills training for the beginners to intermediate surgeons, whichmay serve as a good way for the standardized residency and specialist training program.

关键词： Multi-screen collaboration Dry-lab Laparoscopic simulator Laparoscopic skills Training

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NUMERICAL MODELLING OF THE QUASI-GLOBAL OCEAN CIRCULATION BASED ON POM

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Journal of Hydrodynamics 2004年第5期16卷 537-543页

作者： XIAChang-shui QIAOFang-li ZHANGQing-hua YUANYe-li KeyLaboratoryofMarineScienceandNumericalModeling TheFirstInstituteofOceanographyStateOceanicAdministrationQingdao266061China

A free surface quasi-global ocean circulation model, Princeton Ocean Model(POM), was adopted to simulate the climatological circulation. The horizontal resolution of themodel was 1/2° x 1/2° with 16 vertical sigma layers. The initial temperature and salinity fieldsof the model were interpolated from the Levitus data, and the COADS (Comprehensive Ocean-AtmosphereData Set) monthly mean SST and wind fields were used as the surface forcing. The integral timelength is 6a. The main general circulation components such as the equatorial current, the equatorialundercurrent, the south and north equatorial currents, the Antarctic Circumpolar Current (ACC), theKuroshio and the Gulf Stream were well reconstructed. The volume transports of PN section and ACCa-gree well with the estimations on field survey. Up to now there is no global or quasi-globalcirculation model results u-sing POM in literature. Our results demonstrate that POM has soundability to simulate the coastal circulation as well as the general ocean circulation. And thisresult can provide open boundary conditions for fine resolution regional ocean circulation models.

关键词： ocean circulation numerical model princeton ocean Model (POM)

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