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Fatigue Properties of RPC under Cyclic Loads of Single-stage and Multi-level Amplitude

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Journal of Wuhan University of Technology(Materials Science) 2010年第1期25卷 167-173页

作者：安明喆 School of Civil Engineeringss Beijing Jiaotong University

Fatigue properties of Reactive Powder Concrete （RPC） under axial compression of single-stage and multi-level amplitude in cycles were studied. The tests reveal the fatigue life, the strain and residual life of the RPC samples. Through the analysis of the test results under cyclic loads of single amplitude, the S-N curve of RPC and the evolution rule of macro-damage of RPC were presented, which can be divided into latency stage, stable development stage and instability development stage according to the evolution pattern of the fatigue crack. Accordingly, the development of longitudinal deformation presents the similar three-stage-model, and the proportion of each stage is 15%, 75%, and 10%. According to test results, the fatigue strength reduction factor is 0.564. We brought forward an empirical formula to predict the life of RPC via total longitudinal strain and got the evolving rule for the residual strength of the RPC. The analysis of the test results under cyclic loads of multi-level amplitude shows that the strain under this loading pattern experiences three stages. The characteristic value for the residual strain was obtained. The irreversible damage and non-linear evolution of RPC was described by the development of the residual plastic strain.

关键词： Reactive Powder Concrete (RPC) single-stage amplitude multi-level amplitude fatigue

Preparation of Diphenylcarbazide-Directed Cd Se Quantum Dots and Selective Determination for Cr(Ⅵ)

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Journal of Wuhan University of Technology(Materials Science) 2016年第5期31卷 972-976页

作者：石岩 SUN Ken School of Environmental and Municipal Engineering North China University of Water Resources and Electric Power Zhengzhou 450045China Farmland Irrigation Research Institute CAAS Xinxiang 453002 China

Cd Se quantum dots（QDs） were synthesized using diphenylcarbazide（DL） to sequester QDs precursors（Cd^（2＋）） in situ. Fluorescence（FL） analysis showed the successive synthesis of QDs could be realized by capping with DL and the binding between DL and Cd^（2＋）. The average QDs particle size was about 5-20 nm by high-resolution transmission electron microscopy（HRTEM）. Fourier transform infrared（FT-IR） spectra showed that Cd Se QDs could be chemically bonded with DL. The formation of QDs-DL-Cr（Ⅵ） could lower the fluorescence intensity of QDs. In a certain concentration range, the fluorescence intensity and Cr（Ⅵ） concentration presented a linear relationship. As a result, this phenomenon could be used to determine the Cr（Ⅵ） concentration in the range of 0-24 ×10^（-6） mol· L^（-1）.

关键词： Cr(Ⅵ) CdSe quantum dots fluorescence linear relationship

Spatial interpolation of orchard soil pH using soil type and planting duration as auxiliary information

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Pedosphere 2020年第5期30卷 628-637页

作者： Chuancheng FU Haibo ZHANG Chen TU Lianzhen LI Xinghua LIU Yongming LUO CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation Yantai Institute of Coastal Zone ResearchChinese Academy of SciencesYantai 264003(China) University of Chinese Academy of Sciences Beijing 100049(China)

Intensified field management in orcahrds has resulted in significant and widespread acidification in the ***,effectively mapping the spatial patterns of soil pH aiming to support ecological management is impeded by its large variotions across soil types and planting *** methods were used to integrate soil type and planting duration information for effective mapping of orchard soil pH in a case study in orchards of the Northeast Jiaodong Peninsula,East china.A total o f 1472 surface soil samples were collected,and the planting duration o f each sampled orchard was acquired to generate a planting duration map via Voronoi *** performance of five kriging methods was compared,namely,ordinary kriging(OK),OK combined with soil type(OK_ST),OK combined with planting duration(OK_PD),cokriging combined with soil type and planting duration(OCK_STPD),and OK combined with soil type and planting duration(OK_STPD).Results showed that soil pH declined significantly with increasing planting duration and exhibited moderate spatial variability over the study *** type and planting duration both had significant influence on the spatial distribution of soil *** OCK_STPD and OK_STPD methods showed better prediction efficiency than OK,OK_ST,or OK_*** regard to the predicted maps of soil pH,the OCK_STPD and OK_STPD methods highly reflected local variations associated with soil type and planting duration,but the OK method was poorly *** soil type and planting duration information may be used as ancillary information to improve the mapping quality o f orchard soil *** OCK_STPD and OK_STPD methods were practical and efficient methods for interpolating orchard soil pH in the study *** resultant high-quality soil pH maps can contribute to improved site-specific management in the orchards.

关键词： Jiaodong Peninsula cokriging kriging orchard soil properties soil acidification soil map

Adhesion of pathogenic Vibrio alginolyticus to the gill mucus of Pseudosciaena crocea

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Acta Oceanologica Sinica 2007年第3期26卷 101-109页

作者： CHEN Qiang YAN Qingpi MA Shen ZHUANG Zhixia WANG Xiaoru Fisheries College Jimei University Xiamen 361021 China Fisheries College Ocean University of China Qingdao 266003 China First Institute of Oceanography State Oceanic Administration Qingdao 266061 China

Adhesion of Vibrio alginolyticus to the gill mucus of Pseudosciaena crocea has been investigated using [ methyl-^3 H ] thymidine as isotope tracer. The results showed that： the adhesive quantity of V. alginolyticus increased with bacterial concentrations and reached equilibrium after incubated for 180 min; the higher adhesive quantity was obtained at 15 ~ 30 ℃ and sourish conditions; adhesion of V. alginolyticus could not achieved without Na^＋ , and Ca^2＋ played an auxiliary role in the bacterial adhesion; adhesion of V. alginolyticus was inhibited remarkably by starvation, heat treatment and periodic acid treatment; all of the eight kinds of carbohydrates investigated enhanced the adhesion of V. alginolyticus to the gill mucus of P. crocea, among them, glucose, mannose, fructose and maltose showed the specially enhanced adhesion. The results indicated that E alginolyticus could adhere to the gill mucus of P. crocea facilely in seawater, and this bacterial adhesion was influenced by environmental factors and closely related to superficial carbohydrate structures and some heat-sensitive structures.

关键词： Vibrio alginolyticus adhesion Pseudosciaena crocea gill mucus

Effect of Fe Particle on the Surface Peeling in Cu-Fe-P Lead Frame

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Journal of Wuhan University of Technology(Materials Science) 2006年第3期21卷 18-20页

作者：苏娟华 College of Materials Science and Engineering Henan University of Science and Technology Luoyang 471003ChinaCollege of Materials Science and Engineering Northwestern Polytechnical University Xi'an 710072China

Under the surface peeling of Cu- Fe- P lead frame alloy larger Fe particles were observed by energy dispersive spectroscopy. By using the large strain two-dinension plane strain model and elastic plastic finite element method, the cause for peeling damage of Cu-Fe-P lead frame aUoy was investigated. The results show that when the content of Fe particles is more than 30% at local Fe-rich area the intense stress coacentration in the Fe particle would make the Fe particle broken up. The high equivalent stress mutation and the mismatch of equivalent strain 10% at the two sides of intefrace make it easy to develop the crack and peeling damage on finish rolling. The larger Fe particles in the Cu-Fe-P alloy should be avoided.

关键词： Cu-Fe-P lead frame surface peeling equivalent Stress equivalent strain

Comparative analysis of the Monochamus alternatus immune system

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Insect Science 2018年第4期25卷 581-603页

作者： Jiao Zhou Hai-Ying Yu Wei Zhang Faheem Ahmad Song-Nian Hu Li-Lin Zhao Zhen Zou Jiang-Hua Sun State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of Zoology Chinese Academy of Sciences Beijing China CAS Key Laboratory of Genome Sciences and Information Beijing Institute of Genomics Chinese Academy of Sciences Beijing China Department of Biosciences COMSA TS Institute of Information Technology Islamabad Pakistan University of Chinese Academy of Sciences Beijing China

The pine sawyer beetle, Monochamus alternatus, is regarded as a notorious for- est pest in Asia, vectoring an invasive pathogenic nematode, Bursaphelenchus xylophilus, which is known to cause pine wilt disease. However, little sequence information is available for this vector beetle. This hampered the research on its immune system. Based on the transcriptome of M. alternatus, we have identified and characterized 194 immunity-related genes in M. alternatus, and compared them with homologues molecules from other species known to exhibit immune responses against invading microbes. The lower number of puta- tive immunity-related genes in M. alternatus were attributed to fewer C-type lectin, serine protease （SP） and anti-microbial peptide （AMP） genes. Phylogenetic analysis revealed that M. alternatus had a unique recognition gene, galectin3, orthologues of which were not identified in Tribolium castaneum, Drosophila melanogastor, Anopheles gambiae and Apis mellifera. This suggested a lineage-specific gene evolution for coleopteran insects. Our study provides the comprehensive sequence resources of the immunity-related genes ofM. alternatus, presenting valuable information for better understanding of the molecular mechanism of innate immunity processes in M. alternatus against B. xylophilus.

关键词： Bursaphelenchus xylophilus expression profiling insect immunity Monochamus alternatus serine protease transcriptome

Switching Delay Aware Computing Resource Allocation in Virtualized Base Station

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china Communications 2016年第11期13卷 226-233页

作者： Mingjin Gao He(Henry) Chen Yonghui Li Yiqing Zhou Jinglin Shi Institute of Computing Technology Chinese Academy of Sciences Beijing 100190 China School of Electrical and Information Engineering The University of Sydney NSW 2006 Australia University of Chinese Academy of Sciences Beijing 100049 China Beijing Key Laboratory of Mobile Computing and Pervasive Device Beijing 100190 China

In centralized cellular network architecture,the concept of virtualized Base Station(VBS) becomes attracting since it enables all base stations(BSs) to share computing resources in a dynamic manner. This can significantly improve the utilization efficiency of computing resources. In this paper,we study the computing resource allocation strategy for one VBS by considering the non-negligible effect of delay introduced by switches. Specifically,we formulate the VBS's sum computing rate maximization as a set optimization problem. To address this problem,we firstly propose a computing resource schedule algorithm,namely,weight before one-step-greedy(WBOSG),which has linear computation complexity and considerable performance. Then,OSG retreat(OSG-R) algorithm is developed to further improve the system performance at the expense of computational complexity. Simulation results under practical setting are provided to validate the proposed two algorithms.

关键词： virtualized base station parallel computing computing resource allocation C-RAN

Properties of Boron-doped μc-Ge:H Films Deposited by Hot-wire CVD

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Journal of Wuhan University of Technology(Materials Science) 2015年第3期30卷 516-519页

作者：黄海宾沈鸿烈 WU Tianru LU Linfeng TANG Zhengxia SHEN Jiancang Institute of Photovoltaics Nanchang University College of Materials Science & Technology Nanjing University of Aeronautics & Astronautics national Laboratory of Solid State Microstructure and Department of Physics Nanjing University

Boron-doped hydrogenated microcrystalline Germanium （lac-Ge：H） films were deposited by hot-wire CVD. H2 diluted G-ell4 and B2H6 were used as precursors and the substrate temperature was kept at 300 ℃. The properties of the samples were analyzed by XRD, Raman spectroscopy, Fourier transform infrared spectrometer and Hall Effect measurement with Van der Pauw method. It is found that the films are partially crystallized, with crystalline fractions larger than 45% and grain sizes smaller than 50 nm. The B-doping can enhance the crystallization but reduce the grain sizes, and also enhance the preferential growth of Ge （220）. The conductivity of the films increases and tends to be saturated with increasing diborane-to-germane ratio RB2H6. All the Hall mobilities of the samples are larger than 3.8 cmZV-1·s-1. A high conductivity of

关键词： Boron pc-Ge:H film HWCVD crystalline fraction conductivity Hall mobility

Mechanism of Boron Oxide as a Phase Regulator for Modification of Manganese Slag

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Journal of Wuhan University of Technology(Materials Science) 2014年第1期29卷 89-92页

作者：陈平 LI Zhibo 刘荣进 XIANG Weiheng QI Aixiang College of Materials Science and Engineering Guilin University of Technology Key Lab of New Processing Technology for Nonferrous Metals & Materials Minstry of Education Guang Xi Key Laboratory of New Energy and Building Energy Saving University of Science and Technology Beijing

The current research focused on adjusting the low hydration activity of the metallurgical slag by phase reconstruction technique. Boron oxide was used as a phase regulator to improve the amorphous phase composition of the manganese slag, consequently enhancing its hydraulic activity. The effects of boron oxide dosage and calcination temperature on the manganese slag amorphous phase content were investigated. XRD and DTG were performed to analyze the hydration mechanism of the manganese slag powder and cement. Results show that, when boron oxide dosage is 15%, calcination temperature is 1 300℃, and holding time for 1 hour, the amorphous content of the modified manganese slag reaches 95% and its 28-day activity index reaches 8 1.7%. The manganese slag powder can then be used as cement or concrete admixtures for the building materials industry.

关键词： boron oxide manganese slag amorphous content hydraulic activity