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Wear behavior of bainite ductile cast iron under impact load

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International Journal of Minerals,Metallurgy and Materials 2014年第9期21卷 871-877页

作者： Ting Sun Ren-bo Song fu-qiang yang Chun-jing Wu School of Materials Science and Engineering University of Science and Technology Beijing

The dry impact wear behavior of bainite ductile cast iron was evaluated under three different impact loads for 30000 cycles. The strain-hardening effects beneath the contact surfaces were analyzed according to the surfaces＇ micro-hardness profiles. Scanning electron microscopy （SEM） and X-ray diffraction （XRD） were used to observe the wom surfaces. The results indicated that the material with the highest hardness was the one continuously cooled at 20℃, which exhibited the lowest wear rate under each set of test conditions. The hardness of the worn surface and the thickness of the hardened layer increased with the increases in impact load and in the number of test cycles. The better wear performance of the sample cooled at 20℃ is attributed to its finer microstructure and superior mechanical properties. All the samples underwent the transformation induced plasticity （TRIP） phenomenon after impact wear, as revealed by the fact that small amounts of retained austenite were detected by XRD.

关键词： cast iron continuous cooling wear behavior impact loads martensitic transformations

Three-dimensional weighting reconstruction algorithm for circular cone-beam CT under large scan angles

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Nuclear Science and Techniques 2017年第8期28卷 75-82页

作者： Ya-Fei yang Ding-Hua Zhang Kui-Dong Huang fu-qiang yang Zong-Zhao Gao Key Lab of Contemporary Design and Integrated Manufacturing Technology (Northwestern Polytechnical University) Ministry of Education Xi'an 710072 China

Improving imaging quality of cone-beam CT under large cone angle scan has been an important area of CT imaging research. Considering the idea of conjugate rays and making up missing data, we propose a three-dimensional(3D) weighting reconstruction algorithm for cone-beam CT. The 3D weighting function is added in the back-projection process to reduce the axial density drop and improve the accuracy of FDK algorithm. Having a simple structure, the algorithm can be implemented easily without rebinning the native cone-beam data into coneparallel beam data. Performance of the algorithm is evaluated using two computer simulations and a real industrial component, and the results show that the algorithm achieves better performance in reduction of axial intensity drop artifacts and has a wide range of application.

关键词：重建算法锥束CT 三维角度扫描加权性能评价轴向强度 FDK算法

Hot Deformation and Dynamic Recrystallization Behavior of Austenite-Based Low-Density Fe–Mn–Al–C Steel

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Acta Metallurgica Sinica(English Letters) 2016年第5期29卷 441-449页

作者： Ya-Ping Li Ren-Bo Song Er-Ding Wen fu-qiang yang School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China R&D Center BAIC Motor Corporation LTDBeijing 101300China

The hot deformation and dynamic recrystallization （DRX） behavior of austenite-based Fe-27Mn-ll.5A1- 0.95C steel with a density of 6.55 g cm-3 were investigated by compressive deformation at the temperature range of 900-1150 ℃ and strain rate of 0.01-10 s-1. Typical DRX behavior was observed under chosen deformation conditions and yield-point-elongation-like effect caused by DRX of 6-ferrite. The flow stress characteristics were determined by DRX of the 6-ferrite at early stage and the austenite at later stage, respectively. On the basis of hyperbolic sine function and linear fitting, the calculated thermal activation energy for the experimental steel was 294.204 kJ mo1-1. The occurrence of DRX for both the austenite and the 6-ferrite was estimated and plotted by related Zener-Hollomon equations. A DRX kinetic model of the steel was established by flow stress and peak strain without considering dynamic recovery and 6-ferrite DRX. The effects of deformation temperature and strain rate on DRX volume fraction were discussed in detail. Increasing deformation temperature or strain rate contributes to DRX of both the austenite and the 6-ferrite, whereas a lower strain rate leads to the austenite grains growth and the 6-ferrite evolution, from banded to island-like structure.

关键词： Fe-Mn-AI-C steel Hot deformation Dynamic recrystallization Yield-point-elongation-likeeffect

A dual measurement method of strain and temperature

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Journal of Marine Science and Application 2007年第1期6卷 63-68页

作者： JIANG Hai-li SUN Wei-min ZHANG Cong LIU Zhi-hai JIANG fu-qiang ZHANG yang College of Science Harbin Engineering University Harbin 150001 China

With the rapid development of China's foreign trade, the coastal and inland waterway transport has been increased rapidly. The potential market for marine engines is more and more obvious. The measurement of the engine temperature and strain becomes very important. The fluorescence fiber sensors are broadly used to measure temperature, concentration, and pH value, etc. The fluorescence sensing systems are based on different principles, namely fluorescence intensity, fluorescence intensity ratio, and fluorescence lifetime. The fluorescence lifetime is an effective parameter for sensing purpose, because it is independent of the intensity of the pumping source and does not need expensive narrow-band filters. An experiment system has been established, in which some samples were produced to measure the fluorescence lifetime and temperature characteristics and the relationship of the strain and temperature versus the fluorescence lifetime was achieved at the same time. The experiment result was fitted and analyzed. The test results show that the fluorescence lifetime decreases with the increasing of temperature. The change of fluorescence lifetime with the strain is inconspicuous comparing to that with the temperature.

关键词： fluorescence lifetime fluorescence fiber simultaneous measurement temperature strain

Mechanism of mechanical activation for spontaneous combustion of sulfide minerals

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Transactions of Nonferrous Metals Society of China 2013年第1期23卷 276-282页

作者：阳富强吴超福州大学环境与资源学院福州350108 中南大学资源与安全工程学院长沙410083

In order to uncover the intrinsic reasons for spontaneous combustion of sulfide minerals,representative samples were collected from typical metal mines to carry out the mechanical activation *** structures and heat behaviors of activated samples were characterized by scanning electron microscopy（SEM）,X-ray diffraction（XRD） analysis,and simultaneous thermal analysis（STA）.It is found that the sulfide minerals after mechanical activation show many changes with increased specific surface areas,aggregation phenomenon,decreased diffraction peak intensity,broadened diffraction peak,declined initial temperatures of heat release and self-ignition points.A new theory for explaining the spontaneous combustion of sulfide minerals is put forward：the chemical reaction activity of sulfide minerals is heightened by all kinds of mechanical forces during the mining,and the spontaneous combustion takes place finally under proper environment.

关键词： metal mines mining sulfide minerals spontaneous combustion mechanical activation reaction mechanism chemical reaction activity

Quantum　Chemistry　Studies　on　the　Heteropoly　Blues　of　Molybdosilic　Series　with　α-Keggin　Structure

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Chemical Research in Chinese Universities 1997年第3期13卷 262-267页

作者： fu qiang, yang Ming , CHEN Bin , WANC En-Bo, XIE De-Min , JIANG Zhong-Ming,PENG Jun (Department of Chemistry,Northeast Normal University,Changchun,130024) NE NORMAL UNIV DEPT CHEMCHANGCHUN 130024PEOPLES R CHINA

SCC-DV-X method was used for the theoretical calculation of heteropoly an- ion , [SiMoO40]4- . and heteropoly blue anions,[SiMo2 Mo10O40]6 and [SiMo4 Mo!; O' 1,-. Th. ***.. .ol...l.. orbital. , orbital ***.. , *** 1...l. , the o.- cupied numbers of basis functions , free valences , Mulliken populations and the fig- ure of the total density of states have been obtained. The theoretical analysis indi- cates that all the atoms in the anions participate in chemical reactions , but Oc and Od have higher chemical activities than other atonts , which is supported by the ex- perimental results. The heteropoly hue anions with the α-Keggin structure distort a little and the levels of valence orbitals demonstrate that [SiMo4 Mo8O40]8 can form a six-electron heteropoly blue anoint by accepting two electrons.

关键词： SCC-DV-X method α-Keggin structure Fermi level Mulliken popu- lations

基于专利时效性和PageRank算法的企业技术影响力评价

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系统管理学报 2018年第2期27卷 352-358页

作者：傅强孙杨重庆大学经济与工商管理学院重庆400075

借鉴链接分析中PageRank算法及其在技术影响力评价体系中的应用,创新性地考虑专利时效性,改进了基于专利引用关系的企业引用网络的技术影响力评价方法。使用美国国家经济研究局NBER专利数据库中1976~2006年实用型液压制动领域的专利明... 详细信息

借鉴链接分析中PageRank算法及其在技术影响力评价体系中的应用,创新性地考虑专利时效性,改进了基于专利引用关系的企业引用网络的技术影响力评价方法。使用美国国家经济研究局NBER专利数据库中1976~2006年实用型液压制动领域的专利明细及引用关系等为样本进行了实证分析。结果显示,与不考虑时效性的技术影响力评价体系相比,提出的改进评价算法综合考虑了引用企业数量、被引次数、企业自身影响力、企业间依赖程度和专利时效性5个方面的因素,能够更为客观地评价领域内企业的技术影响力,为识别技术竞争对手提供了理论依据。

关键词：企业技术引用关系影响力评价专利引用 PageRank 时效性

The Application of PPE Model Based on RAGA in Benefit Evaluating of Rice Water Saving

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Journal of Northeast Agricultural University(English Edition) 2003年第2期10卷 141-146页

作者： fu qiang,yang Guang-lin,fu Hong(Northeast Agricultural University,Harbin,Heilongjiang,150030,PRC) Northeast Agricultural University HarbinHeilongjiang150030PRC

Through applying PPE model based on RAGA to evaluate the benefit of rice water saving,the author turns multi-dimension data into low dimension *** the optimum projection direction can stand for the best influence on the ***,the value of projection function can evaluate each item good or *** PPE model can avoid jamming of weight matrix in the method of fuzzy synthesize judgement,and obtain better *** author wants to provide a new method and thought for readers who are engaged in investment decision-making of water saving irrigation and other relative study.

关键词： RAGA PPE benefit of water saving irrigation evaluation

Phase Ⅱb trial of in vivo electroporation mediated dualplasmid hepatitis B virus DNA vaccine in chronic hepatitis B patients under lamivudine therapy

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World Journal of Gastroenterology 2017年第2期23卷 306-317页

作者： fu-qiang yang Gui-Rong Rao Gui-qiang Wang Yue-Qi Li Yao Xie Zhan-Qing Zhang Cun-Liang Deng Qing Mao Jun Li Wei Zhao Mao-Rong Wang Tao Han Shi-Jun Chen Chen Pan De-Ming Tan Jia Shang Ming-Xiang Zhang Yue-Xin Zhang Ji-Ming yang Guang-Ming Chen Liver Disease Research Center 458~(th) Hospital of PLA Department of Infectious Diseases Peking University First Hospital Beijing 302 Hospital Ninth Clinical Department Beijing Ditan Hospital Department of Liver Diseases Public Health Center Fudan University Department of Infectious Diseases Affiliated Hospital of Luzhou Medical College PLA Institute of Infectious Diseases Southwest Hospital Third Military Medical University Jiangsu Province People’s Hospital Nanjing 2~(nd) Hospital Nanjing PLA 81 Hospital Tianjin 3~(rd) Center Hospital Jinan Infectious Disease Hospital fuzhou Infectious Disease Hospital Xiangya Hospital Central South University Henan Provincial People’s Hospital The Sixth People’s Hospital of Shenyang The First Affiliated Hospital of Xinjiang Medical University Infectious Disease Hospital of Tianjin

AIM To assess the efficacy and safety of in vivo electroporation(EP)-mediated dual-plasmid hepatitis B virus(HBV) DNA vaccine vs placebo for sequential combination therapy with lamivudine(LAM) in patients with chronic hepatitis B. METHODS Two hundred and twenty-five patients were randomized to receive either LAM + vaccine(vaccine group, n = 109) or LAM + placebo(control group, n = 116). LAM treatment lasted 72 wk. Patients received the DNA vaccine or placebo by intramuscular injection mediated by EP at weeks 12(start of treatment with vaccine or placebo, SOT), 16, 24, and 36(end of treatment with vaccine or placebo, EOT). RESULTS In the modified intent-to-treat population, morepatients had a decrease in HBV DNA > 2 log10 IU/m L in the vaccine group at week 12 after EOT compared with the control group. A trend toward a difference in the number of patients with undetectable HBV DNA at week 28 after EOT was obtained. Adverse events were similar. In the dynamic per-protocol set, which excluded adefovir(ADV) add-on cases at each time point instantly after ADV administration due to LAM antiviral failure, more patients had a decrease in HBV DNA > 2 log10 IU/mL in the vaccine group at week 12 and 28 after EOT compared with the control group. More patients with undetectable HBV DNA at week 28 after EOT in the vaccine group were also observed. Among patients with a viral load < 1000 copies/mL at week 12, more patients achieved HBeA g seroconversion in the vaccine group than among controls at week 36 after EOT, as well as less virological breakthrough and YMDD mutations. CONCLUSION The primary endpoint was not achieved using the HBV DNA vaccine. The HBV DNA vaccine could only be beneficial in subjects that have achieved initial virological response under LAM chemotherapy.

关键词： Chronic hepatitis B DNA vaccine In vivo electroporation Lamivudine-resistant mutants Randomized placebo-controlled trial