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The effect of environmental variables on atmospheric corrosion of carbon steel in Shenyang

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Chinese Science Bulletin 2009年第19期54卷 3438-3445页

作者： WANG Chuan WANG ZhenYao KE we State Key Laboratory for Corrosion and Protection Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

A study was carried out in order to investigate the effect of contaminants and meteorological variables on the rust layer of carbon steel exposed in Shenyang urban atmosphere. Seven kinds of contaminants and twe.ve kinds of meteorological parameters we.e also registered in order to correlate the data with respect to corrosion rate and the stepwise multiple regression analysis was carried out in order to obtain the best regression model. The sum of rainfall time as we.l as sunshine time and the concentration of H2S could stimulate initial atmospheric corrosion of carbon steel. The initial atmospheric corrosion kinetics of carbon steel was observed to follow the cubic equation. The corrosion products we.e analyzed by XRD and the transformation of phases in different periods was discussed.

关键词：钢铁腐蚀大气环境腐蚀状态沈阳市

Self Localization Method Using Parallel Projection Model for Mobile Sensor in Navigation Applications

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Journal of Computer Science & Technology 2009年第3期24卷 588-603页

作者： Shung Han Cho Yuntai Kyong Sangjin Hong we.Duke Cho Department of Electrical and Computer Engineering Stony Brook University- SUNY Stony Brook NY U.S.A. Department of Electronics Engineering College of Information Technology Ajou University Suwon Korea

This paper presents a novel self localization method using parallel projection model for mobile sensor in navigation applications. The algorithm estimates the coordinate and the orientation of mobile sensor using projected references on visual image. The proposed method considers the lens non-linearity of the camera and compensates the distortion by using a calibration table. The method determines the coordinates and orientations with iterative process, which is very accurate with low computational demand. we.identify various sources of error on the coordinate and orientation estimations, and present both static sensitivity analysis of the algorithm and dynamic behavior of the mobile sensor. The algorithm can be utilized in mobile robot navigation as we.l as positioning application where accurate self localization is necessary.

关键词： mobile sensors localization parallel projection model visual processing

Complete Kaehler Submanifolds in CP^n

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Chinese Quarterly Journal of Mathematics 2005年第2期20卷 214-220页

作者： SONGXiao-xin hucong-e CollegeofMathematicsandInformationScience HenanUniversityKaifeng475001China

In this paper we.mainly investigate projectively flat complete Kaehler submanifolds, in CP^n. we.give the pinching constants and the local structure.

关键词： Kaehler Submanifolds complete scalar curvature

Microstructure and Tensile Properties of 1-D Forged （TiB+TiC）/Ti Composite

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Microstructure and Tensile Properties of 1-D Forged （TiB+Ti...

Taxonomic composition, abundance and biomass of mesozooplankton in the Zhelin Bay—an estuary with intensive aquaculture

中国材料大会2012

作者： Changjiang Zhang Fantao Kong Shulong Xiao Lijuan Xu Yuyong Chen Ningjia Deng we. Ge Guojun Xu National Key Laboratory of Science and Technology on Precision Heat Processing of Metals Harbin Institute of Technology Nanjing Baotai Special Materials CO. LTD.

ISBN: (纸本)9783037856086;3037856084

In this work, 2.5vol. % （TiB+TiC）/Ti composite was prepared by in situ casting route then 1-D forging. The microstructure and tensile properties we.e presented and discussed. The results indicate that the as cast microstructure can be significantly modified by 1-D forging. After forging, TiB and TiC segregated at the prior β grain boundaries within the as-cast composite tend to fracture and align perpendicular to forging direction. Reduction in aspect ratio of reinforcements and lath is also observed. 1-D forging can enhance the strength and elongation of as cast composite significantly. Howe.er, the increment in strength is quite limited as strain temperature increases to 700 ℃. Additionally, room temperature and high temperature fracture mechanisms are also discussed.

关键词： Titanium matrix composites Microstructure Tensile properties Forged.

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Acta Oceanologica Sinica 2006年第5期25卷 92-111页

作者： DONG Qiaoxiang LIN Xiaoping HE Xin KELSO we.HUANG Changjiang School of Environmental Science and Public Health Wenzhou Medical College Wenzhou 325035 China Institute of Marine Biology Shantou University Shantou 515063 China School of Renewable Natural Resources Louisiana State University Agricultural Center Baton Rouge Louisiana 70803 USA

The Zhelin Bay is an estuary that supports intensive aquaculture in South China. Aside from traditional nutrient inputs derived from waste water and agriculture, the increased intensification of aquaculture has accelerated eutrophication during the past deeade, jeopardizing aquacultural production. Annual variations of mesozooplankton in the Zhelin Bay we.e described, providing baseline data for long-term ecological studies. The taxonomic composition, abundance and biomass of mesozooplankton we.e stud- ied monthly from July 2001 to July 2002 at 19 stations. Collections yielded 73 taxa, including 60 species of eopopods, three species of cladocerans, as we.l as tunieates, ehaetognaths, polyehaetes, medusae, ostraceds, rotatori, amphipods, planktonic mollusks, pelagic larvae, and planktonic shrimps. The Zhelin Bay was dominated by small mesozooplankton, with 76% of the species smaller than 1.4 mm, and 97% of the individuals smaller than 1.0 nun. Dominant species （ Paracalanus crassirostris, Oithona brevicornis, and Penilia avirostria） accounting for 60% of the total abundance we.e less than 0.6 mm in body length. Species diversity, biomass, and total abundance of mesozooplankton we.e greater in the samples collected outside the bay than inside the bay. Samples from the outer and eastern boundaries of the bay had greater biomass, diversity, and abundance than those from the inner and we.tern boundaries. Total abundance and biomass had a unimodal annual pattern and we.e the greatest in August 2001 when water temperature was maximum, and the least in February 2002 when water temperature was minimum. Canonical correspondence analysis （CCA） revealed that temperature, turbidity, nutrients and salinity we.e the main determinants of spatial and temporal distributions of mesozooplankton in the Zhelin Bay, and six distinct zones we.e identified across the 19 sampling stations.

关键词： Zhelin Bay mesozooplankton community structure spatial and temporal distribution aquaculture

A Test Method for the Static/Moving State of Targets Applied to Airport Surface Surveillance MLAT System

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Transactions of Nanjing University of Aeronautics and Astronautics 2016年第4期33卷 425-432页

作者： Huang Rongshun Peng we.Li Jing Wu Honggang Li Xingbo The Second Research Institute of Civil Aviation Administration of China College of Electronic Engineering University of Electronic Science and Technology of China

Due to the particularity of its location algorithm,there are some unique difficulties and features regarding the test of target motion states of multilateration(MLAT)system for airport surface *** paper proposed a test method applicable for the airport surface surveillance MLAT system,which can effectively determine whether the target is static or moving at a certain *** a normalized test statistic designed in the sliding data window,the proposed method not only eliminates the impact of geometry Dilution of precision(GDOP)effectively,but also transforms the test of different motion states into the test of different probability density ***,by adjusting the size of the sliding window,it can fulfill different test performance *** method was developed through strict theoretical extrapolation and performance analysis,and simulations results verified its correctness and effectiveness.

关键词： multilateration(MLAT) hypothesis testing motion state detection sliding window geometric Dilution of precision(GDOP)

Association betwe.n the level of CD4^+T lymphocyte microRNA-155 and coronary artery disease in patients with unstable angina pectoris

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Journal of Geriatric Cardiology 2018年第10期15卷 611-617页

作者： Zi-Liang we.Hai-Li LU Qiang SU Lang Li Department of Cardiology the First Affiliated Hospital of Guangxi Medical UniversityGuangxi Cardiovascular InstituteNanningGuangxiChina Department of Orthodontics the Affiliated Dental Hospitdl of Guangxi Medical UniversityNanningCruangxiChina

Objective To study the association betwe.n the expression of microRNA-155(miRNA-155)in peripheral blood CD4^+T lymphocytes and the level of semrn interferon-7(IFN-7)concentration and the severity of coronary artery disease (CAD).Methods After coronary angiography,252patients with suspected unstable angina pectoris (UAP)we.e divided into the UAP group (128patients with CAD confirmed by angiography)and the control group (124patients without CAD confirmed by angiography).Fresh peripheral blood was extracted 16-24h before coronary angiography,CD4^+T lymphocytes was tested using immunomagnetic beads,the expression ofmiRNA-155was tested using quantitative PCR and the expression of IFN-7was tested using enzyme-linked immunosorbent assay (ELISA).According to the results of angiography,Gensini score of coronary artery lesions was ***,we.also analysis the association betwe.n the level of miRNA-155in peripheral blood CD4^+T lymphocytes,the level of serum IFN-γand Gensini score of coronary *** The levels ofmiRNA-155(0.49±0.08vs.0.23±0.09)and IFN-7(227.58±26.01vs.141.23±17.89)in the UAP group we.e significantly higher than that of the control group,the difference was statistically *** level of miRNA-155and IFN-γwe.e positively correlated with Gensini score of CAD (r =0.534,r =0.713,respectively,all P <0.05).The level of miRNA-155was positively correlated with the level of IFN-γ,(r =0.686,P <0.05).Conclusions The level of miRNA-155in peripheral blood CD4^+T lymphocytes and the level of IFN-γ are closely correlated with the severity of CAD.

关键词： CD4^+T lymphocyte Coronary artery disease IFN-γ MicroRNA-155

In-Depth Computational Analysis of Natural and Artificial Carbon Fixation Pathways

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BioDesign Research 2021年第1期2021卷 96-118页

作者： Hannes Löwe.Andreas Kremling Systems Biotechnology Technical University of MunichGermany

In the recent years,engineering new-to-nature CO_(2)-and C1-fixing metabolic pathways made a leap ***,artificial pathways promise higher yields and activity than natural ones like the Calvin-Benson-Bassham(CBB)*** question remains how to best predict their in vivo performance and what actually makes one pathway“better”than *** this context,we.explore aerobic carbon fixation pathways by a computational approach and compare them based on their specific activity and yield on methanol,formate,and CO_(2)/H_(2)considering the kinetics and thermodynamics of the *** pathways found in nature or implemented in the laboratory,this included two completely new cycles with favorable features:the reductive citramalyl-CoA cycle and the 2-hydroxyglutarate-reverse tricarboxylic acid cycle.A comprehensive kinetic data set was collected for all enzymes of all pathways,and missing kinetic data we.e sampled with the Parameter Balancing *** and thermodynamic data we.e fed to the Enzyme Cost Minimization algorithm to check for respective inconsistencies and calculate pathway-specific *** specific activities of the reductive glycine pathway,the CETCH cycle,and the new reductive citramalyl-CoA cycle we.e predicted to match the best natural cycles with superior productsubstrate ***,the CBB cycle performed better in terms of activity compared to the alternative pathways than previously *** make an argument that stoichiometric yield is likely not the most important design criterion of the CBB ***,alternative carbon fixation pathways we.e paretooptimal for specific activity and product-substrate yield in simulations with C1 substrates and CO_(2)/H_(2)and therefore hold great potential for future applications in Industrial Biotechnology and Synthetic Biology.

关键词： argument kinetics thermodynamics

Lensless diffractive imaging with ultra-broadbandtable-top sources: from infrared to extreme-ultravioletwavelengths

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Light(Science & Applications) 2014年第1期3卷 274-281页

作者： Stefan Witte Vasco T Tenner Daniel we.Noom Kjeld SE Eikema LaserLaB Amsterdam VU University Amsterdam1081 HV AmsterdamThe Netherlands Present address:Huygens-Kamerlingh Onnes Laboratorium Universiteit Leiden2333 CA LeidenThe Netherlands

Lensless imaging is an approach to microscopy in which a high-resolution image of an object is reconstructed from one or more measured diffraction patterns,providing a solution in situations where the use of imaging optics is not ***,current lensless imaging methods are typically limited by the need for a light source with a narrow,stable and accurately known *** have developed a general approach to lensless imaging without spectral bandwidth limitations or sample *** use two time-delayed coherent light pulses and show that scanning the pulse-to-pulse time delay allows the reconstruction of diffraction-limited images for all the spectral components in the *** addition,we.introduce an iterative phase retrieval algorithm that uses these spectrally resolved Fresnel diffraction patterns to obtain high-resolution images of complex extended *** demonstrate this two-pulse imaging method with octave-spanning visible light sources,in both transmission and reflection geometries,and with broadband extreme-ultraviolet radiation from a high-harmonic generation *** approach enables effective use of low-flux ultra-broadband sources,such as table-top high-harmonic generation systems,for high-resolution imaging.

关键词： coherent diffractive imaging extreme ultraviolet Fourier transform spectroscopy high-harmonic generation lensless imaging