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NMR Research on Cement Clinker and Its Structures in Early Age Hydration

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Journal of Wuhan University of technology(Materials Science) 2011年第5期26卷 972-977页

作者：王晓钧 college of Materials Science and Engineering Nanjing University of Technology

Clinker has long been regarded as a critical factor for cement hydration and solidification.α-C2. and β-C2. in 2.aO·SiO2.C2.） phase and C3S Monoclinic 1（C3S M1） and C3S Monoclinic 3 （C3S M3） in 3CaO·SiO2.（C3S） phase were clearly recorded in the 2.Si MAS NMR *** content of C3S phase in the clinker deduced from the fine peak analysis coincides with the phase quantification analysis calculated by the Taylor-Bogue method based on XRF,which also accords to the statistical data in industrial *** provides a proof that C3S M1 and β-C2. phases have a prior reaction in the early age hydration of clinker,and demonstrates that aluminum coordination changes from tetracoordinated 4CaO·Al2.3·Fe2.3（C4AF） to hexacoordinated [Ca2.l（OH）6]（SO4）0.3·3H2.（Aft） in one day hydration and changes to the 3CaO·Al2.3·CaSO4·nH2. （Afm） in a seven-day hydration.

关键词： NMR clinker cement hydration

Influence of MgO-type Expansive Agent Hydration Behaviors on Expansive Properties of Concrete

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Journal of Wuhan University of technology(Materials Science) 2011年第2期26卷 345-347页

作者：卢小琳 college of Materials Science and technology Nanjing University of Aeronautics & Astronautics

The hydration behaviors and expansive properties of MgO-type expansive agent curing at different temperatures and environment were *** the curing temperatures changed from 2.℃ to 50℃,the conductivities of MgO samples increased from 40 to 80 μs/cm,and the hydrations of MgO were quickened up *** SEM observation,the hydration product of MgO cured at 50℃ for 2. day was about 2.3μm in *** expansion of pastes with 5% of the MgO-type expansive agent was from 0.36% to 1.01% when the curing temperature changed from 2.oC to 50℃.When 8% of the MgO-type expansive agent was added,the early shrinkage of concrete was *** expansion ratio increased with the curing temperature,and the expansive cracking of concrete with MgO-type expansive agent might be decreased by blending fly ash.

关键词： concrete expansive agent expansion hydration conductivity

Special magnetic phenomena in heavily doped La_(0.7-x)Dy_xSr_(0.3)MnO_3 system

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Science china(Physics,Mechanics & Astronomy) 2008年第1期51卷 90-97页

作者： LIU Ning 1,2.,YAN GuoQing 1,3 ,CAI ZhiRang 1 ,PI Li 2.,ZHANG Bei 2.&TONG Wei 2.1 Department of Physics,Suzhou college,Suzhou 2.4000,china 2.Structure Research Laboratory,University of Science and {2. of china,Hefei 2.002.,china 3 National Laboratory of Solid State Microstructures,Physics Department,nanjing University,nanjing 2.0093,china Department of Physics Suzhou College Suzhou China Structure Research Laboratory University of Science and Technology of China Hefei China National Laboratory of Solid State Microstructures Physics Department Nanjing University Nanjing China

The magnetism in heavily Dy doped La0.7-xDyxSr0.3MnO3(0.40≤x≤0.70)system is studied in this *** M-T relation seems to be complicated with the increase of *** sample with x=0.40,AFM behavior exists at T≤TN and M-T curves under zero field cooling(ZFC)and field cooling(FC)exhibit typical behavior of spincluster glass state above *** the sample with x=0.50,the M-T curve under ZFC exhibits a valley at a low temperature while the M-T curve under FC exhibits the negative magnetization below *** samples with x=0.60,0.70,their ZFC M-T curves are similar to that of x=0.50,but the FC M-T curves do not exhibit negative values any *** the peculiar phenomena above are well explained by Néel double-lattice model combined with M-H relation at typical *** molecular field theory fits well the negative magnetization for x=0.50.

关键词： heavily doped special magnetic phenomena double-lattice model

Alkali-silica Reactivity of Different Aggregates from Mineral and Textural Characteristics

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Journal of Wuhan University of technology(Materials Science) 2008年第6期23卷 901-906页

作者：莫祥银 Analysis and Testing Center & Jiangsu Key Laboratory of Biofunctional Materials Nanjing Normal University

To identify the aggregates causing the alkali-silica reaction, and the reactivity of rocks in different parts of china, the mineral and texture characteristics of some typical coarse ag gregates and the alkali reactivity of these aggregates were systematically investigated. On one hand, petrographic examination of aggregates, combined with X-ray diffraction analysis, chemical analysis, scanning electron microscopy, was conducted for analyzing their mineralogy and texture. It was found that not only mineral characteristics, but also their interior structure would affect their potential alkali-silica reactivity. Furthermore, the alkali-silica reactivity of aggregates is due to their mineral compositions, such as containing different alkali-reactive minerals, while, different stuctures of those aggregates with similar minerals affect their reactivity to some extent. There are some amount of micro-aperture and cracks across the quartz in the aggregate, which may become the natural accesses for Na^＋, K^＋, and OH^- ions to intrude in the mortar or concrete during the process of alkali-silica reaction. Alkali-silica reactivity of the aggregates was detected by the accelerated mortar bars test. It was revealed that all the aggregates tested were alkali-silica reactive and the results were also in accordance with their mineral and structure analysis.

关键词： petrographic examination of aggregates study of thin sections x-ray diffraction analysis chemical analysis scanning electron microscopy

Structure and Pozzolanic Activity of Calcined Coal Gangue during the Process of Mechanical Activation

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Journal of Wuhan University of technology(Materials Science) 2009年第2期24卷 326-329页

作者：郭伟 Department of Material Engineering Yancheng Institute of Technology Institute of Material Science and Engineering Nanjing University of Technology

On the basis of analyzing coal gangue＇s chemical and mineral compositions, the structure change of coal gangue during the mechanical activation was investigated by XRD, FTIR, NMR, and the mechanical strength of the cement doped coal gangue with various specific surface area was tested. The experimental results indicate that, the lattice structure of metakaolin in coal gangue samples calcined at 700 ℃ disorganizes gradually and becomes disordered, and the lattice structure of α-quartz is distorted slightly. The pozzolanic activity of the coal gangue increases obviously with its structural disorganization.

关键词： coal gangue mechanical activation structure NMR tetrahedron

Key technologies of new malicious code developments and defensive measures in communication networks

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The Journal of china Universities of Posts and Telecommunications 2010年第4期17卷 69-73页

作者： LI Peng,WANG Ru-chuan ,ZHANG Wei college of Computer,nanjing University of Posts and Telecommunications,nanjing 2.0003,china college of Computer Nanjing University of Posts and Telecommunications Nanjing 210003 China

This article is focused on analyzing the key technologies of new malicious code and corresponding defensive measures in the large-scale communication networks. Based on description of the concepts and development of the malicious code, the article introduces the anti-analysis technology, splitting and inserting technology, hiding technology, polymorph virus technology, and auto production technology of the malicious code trends with intelligence, diversity and integration. Following that, it summarizes the security vulnerabilities of communication networks from four related layers aspects, according to the mechanisms of malicious code in the communication networks. Finally, it proposes rapid response disposition of malicious code attacks from four correlated steps： building up the network node monitoring system, suspicious code feature automation analysis and extraction, rapid active malicious code response technique for unknown malicious code, and malicious code attack immunity technique. As a result, it actively defenses against the unknown malicious code attacks and enhances the security performance of communication networks.

关键词： network security malicious code network attack and defense malicious code defense

b-DAZL:A novel gene in bovine spermatogenesis

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Progress in Natural Science:Materials International 2008年第10期18卷 1209-1218页

作者： Qingbo Zhang~a Qifa Li~(a,*) Jiahuang Li~b Xinfu Li~a Zhenshan Liu~a Dawei Song~a Zhuang Xie~a ~a Laboratory of Animal Reproductive Genetics and Molecular Evolution,college of Animal Science and technology,{2. Agriculture University,{2. 2.0095,china ~b Pharmaceutic Biotechnology Key Laboratory,college of Life Science,{2. University,{2. 2.0093,china Laboratory of Animal Reproductive Genetics and Molecular Evolution College of Animal Science and Technology Nanjing Agriculture University Nanjing 210095 China Pharmaceutic Biotechnology Key Laboratory College of Life Science Nanjing University Nanjing 210093 China

The DAZL gene plays an important role in *** and mutation of this gene has been frequently associated with the sterility in both vertebrates and ***,a cDNA containing the complete open reading frame of DAZL gene,which encodes putative RRM RNA-binding protein,was isolated from bovine tissues by *** isolated gene was referred to as ***-based location analysis showed that b-DAZL is located near the end of chromosome *** b-DAZL gene and its vertebrate homologue shared a high nucleotide similarity (90-94%) in the coding region and in the genomic organization,each consisting of 10 exons and 9 *** protein products contained a highly conserved RNA-binding motif,a unique DAZ repeat, and PUM2.and PABP interacting ***-PCR assay revealed that b-DAZL was expressed in the testis and ***,no signals were detected in the testes of sterile male *** microstructure of the testes of sterile males showed very few spermat- ocytes but mostly somatic *** observations are consistent with the typical phenotype of testes with defective DAZL expression. Subsequent gene detection studies indicated that transcription arrest might lead to a b-DAZL transcript defect in testes of cattle-yaks. Our results suggest that b-DAZL may be involved in spermatogenesis,and that transcription arrest of the gene is associated with male sterility in cattle-yaks.

关键词： Cattle-yak b-DAZL Male sterility Sequence analysis Expression profile

Back analysis of mechanical parameters of roller compacted concrete dam

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Science china(Technological Sciences) 2010年第3期53卷 848-853页

作者： GU ChongShi 1,2.3,LI Bo 1,XU GuangLei 4 &YU Hong 1,2.3 1 State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering,Hohai University,nanjing 2.0098,china 2.2. of Water Conservancy Hydropower,Hohai University,nanjing 2.0098,china 3National Engineering Research Center of Water Resources Engineering Safety,Efficient Utilization and nanjing 2.0098,china 4 nanjing Hydraulic Research Institute,nanjing 2.002.,china State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University Nanjing China college of Water Conservancy Hydropower Hohai University Nanjing China National Engineering Research Center of Water Resources Engineering Safety Efficient Utilization and Nanjing Nanjing China nanjing Hydraulic Research Institute Nanjing China

In view of the diversity and complexity of mechanical parameters of roller compacted concrete dam(RCCD),the uniform design method,partial least-squares regression(PLS)and least squares support vector machine(LSSVM)were applied to the back analysis of RCCD with the use of the complex nonlinear relationship between dam mechanical parameters and dam *** the process of back analysis,the initial samples of parameters were designed with uniform design ***,a transversely isotropic model of RCCD was established by *** *** this model,training samples of LSSVM model could be *** then,the complex nonlinear relationship between relative values of hydraulic components of dam displacements and mechanical parameters was ***,actual relative values of dam hydraulic components are isolated from the measured data of dam displacements by using *** inputting the isolated relative values into LSSVM model,the back analysis values of RCCD mechanical parameters can be *** example analysis showed that mechanical parameters obtained by the above-mentioned back analysis method are reasonable,and the back analysis method is feasible.

关键词： roller compacted concrete dam mechanical parameters back analysis

Distributed modeling of the beginning and ending dates and durations of limited temperatures over the rugged terrain of Chongqing

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Progress in Natural Science:Materials International 2009年第12期19卷 1739-1746页

作者： Xinfa Qiu~a,Guoping Shi~a,Yan Zeng~(b,*),Zongya Bian~a,Jingmei Wei~c a Department of GIS,School of Remote Sensing,nanjing University of Information Science & technology,nanjing 2.0044,china b Jiangsu Institute of Meteorological Sciences,nanjing 2.0008,china c Jinling college,nanjing University,nanjing 2.0089,china Department of GIS School of Remote Sensing Nanjing University of Information Science & Technology Nanjing 210044 China Jiangsu Institute of Meteorological Sciences Nanjing 210008 China Jinling college Nanjing University Nanjing 210089 China

A physically based empirical model was established for the beginning and ending dates(BED) of limited *** used were daily mean temperatures from 34 conventional stations in the Chongqing region,measured from 1961 to *** this model in combination with the distributed modeling results of monthly mean temperatures,we developed a method for creating a distributed simulation of the BED and durations of limited temperatures in the rugged terrain of *** distribution maps were generated at a resolution of 100×100 m for the BED and durations of the limited temperatures of 0,10,15 and *** suggest that the distributed model is able to successfully reveal the macroscopic trends and local *** the modeled BED,the mean absolute bias error is 0.6-2.4 d. Cross-validation and case-year tests show mean absolute bias errors of 1.3-2.8 d and 0.7-2.5 d,*** shows that the simulation results are consistent with the field *** implies that the simulations are as good as observations,thus providing a viable technique for simulating mountainous heat resources using conventional meteorological data.

关键词： Distributed modeling Chongqing Limited temperature Beginning and ending date