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Performance assessment of Alccofine with silica fume,fly ash and slag for development of high strength mortar

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Frontiers of Structural and Civil Engineering 2022年第5期16卷 576-588页

作者： Shivang d.JAYSWAL Mahesh MUNGULE Civil Engineering department Institute of InfrastructureTechnologyResearch and Management(IITRAM)Ahmedabad 380026India

Previous studies on concrete have identified silica fume(SF)as the most effective supplementary material,whereas fly ash(FA)and slag have been identified as economical materials with long term strength *** of blended cement mortar referred to as blended mortar(BM)requires similar *** present study explores the application of Alccofine(AL)as supplementary material and compares its performance with conventional materials namely SF,FA and ground granulated blast furnace slag(GGBS).The mortar specimens with binder to fine-aggregates(b/f)ratio of 1:2 are prepared at water to binder(w/b)ratios of 0.4 and *** strength values and stress-strain curve for control and BM specimens are obtained at 7,28,56,and 90 d curing *** assessment based on strength activity index,k-value method and strength estimation model confirms that AL,despite lower pozzolanic activity,contributes to strength gain,due to reduced dilution *** of stress-strain curves suggests that the effect of w/b ratio is more dominant on the elastic modulus of BM specimens than on control *** observations from the study identify enhanced strength gain,improved elastic modulus and higher energy absorption as key contributions of AL making it a potential supplementary material.

关键词： Alccofine high strength mortar efficiency factor dilution effect

Lag times in toe-to-heel air injection(THAI)operations explain underlying heavy oil production mechanisms

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Petroleum Science 2022年第3期19卷 1165-1173页

作者： Wei Wei Ian d.Gates department of Chemical and Petroleum Engineering University of CalgaryCalgaryAlbertaCanada

From a time value of revenue point of view,it is preferred that the time between reservoir stimulation and oil production response is *** oil combustion processes have a lag time between air injection and liquid production,but the common practice in production data analysis uses simultaneous injection and production data when seeking a relationship between *** this research,the time scales of production for the Kerrobert toe-to-heel air injection(THAI)heavy oil project in Saskatchewan,Canada,is analyzed by using cross correlation analysis,*** delay analysis between air injection and oil *** results reveal two time scales with respect to production response with two distinctive recovery mechanisms:(1)a short time scale response(nearly instantaneous)where oil production peaks right after air injection(directly after opening production well)reflecting cold heavy oil production mechanisms,and(2)a longer time scale(of order of 100-300 days)response where peak production occurs associated with the collective phenomena of air injection,heat generating reactions,heat transfer,and finally,heated mobilized heavy oil drainage to the production *** understanding of the two time scales and associated production mechanisms provides a basis for improving the performance of THAI.

关键词： Heavy oil In situ combustion Toe-to-heel air injection(THAI) Production analysis Lag time

On some aspects of compressive properties and serrated flow in Mg-Y-Nd-Zr alloy

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Journal of Rare Earths 2013年第8期31卷 804-810页

作者： H.Azzeddine d.Bradai Faculty of Physics University of Sciences and Technology Houari BoumedieneBP32 El-Alia Bab Ezzouar 16111 Algiers Algeria

The deformation behavior of the Mg-Y-Nd-Zr （WE54） alloy at temperatures between 25 and 400 ℃ was investigated by uniaxial and plans strain compression tests at strain rate values of 10-2 and 10^-4 s^-1. The results showed that the flow stress had a strong dependency on the loading condition. Yield stress and peak stress decreased with increasing deformation temperature and with decrease in the strain rate for both deformation types. The serration flow behavior was observed markedly at high temperatures and under a strain rate of 10^-4S^-1. The serration amplitude for samples deformed by plans strain compression was larger than that by uni- axial compression. Serrated flow was attributed to the interaction of dislocations with precipitates at 300 ℃ and to dynamic discon- tinuous recrystallization effects at 400 ℃.

关键词： Mg-Y-Nd-Zr (WE54) alloy serrated flow dynamic precipitation hot deformation rare earths

Evaluation of effects of 1,3-dinitrobenzene on sperm motility of hamster using computer assisted semen analysis (CASA)

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Asian Journal of Andrology 2001年第2期3卷 109-114页

作者： L.d.C.Peiris H.d.M.Moore dept. of Zoology University of Colombo Colombo 03 Sri LankaDept. of Molecular Biology and Biotechnology University of Sheffield Sheffield S 10 2TN UK

Aim: To evaluate the effects of 1,3-dinitrobenznene (mdNB) on sperm motility of hamster and to correlate the re-sults with the fertility. Methods: Adult male hamsters were gavaged with one of the 3 dose regimes of mdNB(1.5 mg daily for 4 weeks ,1.5 mg one day a week for 4 weeks and 1.0 mg 3 days a week for 4 weeks). Computerassisted semen analysis (CASA) was used to analyse the sperm motility parameters, curvilinear velocity (VCL) andstraight line velocity (VSL) of sperm in distal corpus epididymides and distal cauda epididymides. In vitro fertilisationwas carried out only for 1.5 mg mdNB daily group to determine the sperm fertilising capacity. Results: There wasa significant reduction in sperm velocity parameters at weeks 3 and 4 after treatment, which was correlated with a de-cline in sperm fertility. Conclusion; Sperm velocity parameters may be used to determine the effect of a toxic insulton the sperm function.

关键词： mdNB sperm motility CASA sperm fertility

Effects of acut and chronic doses of methoxy acetic acid on hamster sperm fertilising ability

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Asian Journal of Andrology 2001年第3期3卷 209-216页

作者： L.d.C.Peiris H.d.M.Moore dept. of Zoology University of Colombo Colombo 03 Sri LankaDept. of Molecular Biology and Biotechnology University of Sheffield Sheffield S10 2TN UK

Aim: To evaluate the effects of acute and chronic doses of methoxy acetic acid (MAA) on in vitro fertilisation byhamster sperm and to correlate the data with the testicular damage. Methods: Adult male hamsters were gavagedwith 3 single doses (0, 80, 160 and 650 mg/kg) and 3 chronic doses (0, 8, 32 and 64 mg/kg daily for 5 weeks) ofMAA in distilled water. After treatment hamsters were killed at weekly intervals and spermatozoa recovered from thedistal cauda epididymides were used to assess the fertilising capacity in vitro. The testes were processed for histologicalexamination. Results; Acute doses showed a significant reduction in sperm fertilising ability from week 3 and 4 af-ter treatment and with the chronic doses, the effects were more extensive and persistent. The results were in correpon-dence with the testicular damages observed. Conclusion: It is evident that both acute and chronic doses of MAAcan impair the sperm function by damaging one or more cell populations in the testis.(Asian J Androl 2001 Sep; 3: 209- 216)

关键词： methoxy acetic acid fertilisation in vitro testis spermatozoa fertility

Solution of nonlinear cubic-quintic duffing oscillators using He’s Energy Balance Method

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第9期10卷 1263-1268页

作者： d.d.GANJI M.GORJI S.SOLEIMANI M.ESMAEILPOUR department of Mechanical Engineering University of Mazandaran

In this study, He＇s Energy Balance Method （EBM） was applied to solve strong nonlinear duffing oscillators with cubic-quintic nonlinear restoring force. The complete EBM solution procedure of the cubic-quintic duffing oscillator equation is presented. For illustration of effectiveness and convenience of the EBM, different cases of cubic-quintic duffing oscillator with different parameters of α,β and y were compared with the exact solution. We found that the solutions were valid for small as well as large amplitudes of oscillation. The results show that the EBM is very convenient and precise, so it can be widely appli- cable in engineering and other sciences.

关键词： Energy Balance Method (EBM) Cubic-quintic duffing equation Oscillator

Seismic fragility assessment of RC frame structure designed according to modern Chinese code for seismic design of buildings

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Earthquake Engineering and Engineering Vibration 2012年第3期11卷 331-342页

作者： d. Wu S. Tesfamariam S.F. Stiemer d. Qin Key Laboratory of Earthquake Engineering and Applied Technique of Guangdong Province Guangzhou 501405 China School of Engineering University of British Columbia Kelowna V1 V 1 V7 Canada dept. of Civil Engineering University of British Columbia Vancouver V6T 1Z4 Canada dept. of Civil Engineering Radio Film and Television Design and Research Institute Beijing 100045 China

Following several damaging earthquakes in China, research has been devoted to find the causes of the collapse of reinforced concrete （RC） building sand studying the vulnerability of existing buildings. The Chinese Code for Seismic design of Buildings （CCSdB） has evolved over time, however, there is still reported earthquake induced damage of newly designed RC buildings. Thus, to investigate modern Chinese seismic design code, three low-, mid- and high-rise RC frames were designed according to the 2010 CCSdB and the corresponding vulnerability curves were derived by computing a probabilistic seismic demand model （PSdM）.The PSdM was computed by carrying out nonlinear time history analysis using thirty ground motions obtained from the Pacific Earthquake Engineering Research Center. Finally, the PSdM was used to generate fragility curves for immediate occupancy, significant damage, and collapse prevention damage levels. Results of the vulnerability assessment indicate that the seismic demands on the three different frames designed according to the 2010 CCSdB meet the seismic requirements and are almost in the same safety level.

关键词： building damage criteria collapse ratio probabilistic seismic demand model (PSdM) fragility curves Chinese Code for Seismic design of Buildings (CCSdB)

Analysis of turbulent MHd Couette nanofluid flow and heat transfer using hybrid dTM-FdM

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Particuology 2016年第3期14卷 95-101页

作者： S. Mosayebidorcheh M. Sheikholeslami M. Hatami d.d. Ganji Young Researchers and Elite Club Najafabad Branch lslamicAzad University Ndjafabad Iran department of Mechanical Engineering Lenjan Branch Islamic Azad University lsfahan Iron department of Mechanical Engineering Babol University of Technology Babol Iran Mechanical Engineering department Engineering and Technical College Esfarayen University Esfarayen North Khorasan lran

Unsteady turbulent magnetohydrodynamic nanofluid hydrothermal treatment is studied. The zero- equation turbulence model is used to simulate turbulent flow. The modeling results obtained by applying the hybrid differential transformation method-finite difference method to solve this problem confirm its viability. An analytical procedure is used for finding the effects of the problem parameters. Results indicate that the average Nusselt number over the lower plate depends linearly on volume fraction of nanofluid, Hall parameter, turbulent Eckert number, and Reynolds number whereas it is inversely proportional on the Hartmann number and the turbulent parameter.

关键词： Turbulent Hall effect Hybrid dTM-FdM Nanofluid Magnetohydrodynarnic couette flow

Burden sharing for CdR: balancing fair liability with feasibility

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National Science Review 2023年第12期10卷 47-48页

作者： Chris d.Jones Met Office Hadley Centre

The basics are clear:climate is changing,it is caused by human activity and it is affecting everyone and everywhere now[1]. The good news is that we know what to do about it—we can stop global temperatures rising further if we stop emitting greenhouse gases. But because some sectors (such as agriculture or aviation)will have ongoing ‘hard-to-abate’ emissions,

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