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Modeling the hydration,viscosity and ultrasonic property evolution of class G cement up to 90℃ and 200 MPa by a scale factor method

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Petroleum Science 2023年第4期20卷 2372-2385页

作者： Li-Jun Sun Xue-Yu Pang Siavash Ghabezloo Hai-Bing Yan School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongPR China Key Laboratory of Unconventional Oil&Gas Development(China University of Petroleum(East China)) Ministry of EducationQingdao266580ShandongPR China Navier Ecole des PontsUniv Gustave EiffelCNRSMarne-la-ValleeFrance CNPC Chuanqing Drilling Engineering Co.Ltd.(CCDC) Chengdu610051SichuanPR China

A comprehensive experimental program has been performed to characterize the hydration and engineering property evolution of a class G oil well cement under various curing temperatures from 30 to 90℃.The progress of hydration was monitored by isothermal calorimetry(atmospheric pressure);the viscosity evolution was measured using a high temperature and high pressure consistometer(up to 200 MPa);the ultrasonic property development was evaluated by an ultrasonic cement analyzer(up to 100 MPa).Test results indicate that the influences of curing temperature and pressure on the hydration,viscosity and ultrasonic property development can be modeled by a scale factor method that is similar to the maturity method used in the concrete ***,the key parameters of the scale factor model,namely the apparent activation energy and the apparent activation volume of cement showed obvious variations with test method and curing *** test results indicate that the curing temperature has a stronger effect on cement hydration rate than viscosity and ultrasonic property development rate,while the curing pressure has a much stronger influence on cement slurry properties before setting(viscosity)than after setting(ultrasonic property).

关键词： Activation energy Activation volume isothermal calorimetry Consistency Ultrasonic property

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Selective binding of divalent cations toward heme proteins

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Frontiers in Biology 2016年第1期11卷 32-42页

作者： Pijush Basak Tanay Debnath Rajat Banerjee Maitree Bhattacharyya Department oJBiochemistry University of Calcutta 35 Ballygunge Circular Road Kolkata-700019 India Department of Chemistry Indian Institute of Chemistry Kanpur Kanpur 208016 U. P. India Department of Biotechnology University of Calcutta35 Ballygunge Circular Road Kolkata-700019 India

Potential toxicity of transition metals like Hg, Cu and Cd are well known and their affinity toward proteins is of great concern. This work explores the selective nature of interactions of Cu2＋, Hg2＋ and Cd2＋ with the heme proteins leghemoglobin, myoglobin and cytochrome C. The binding profiles were analyzed using absorbance spectrum and steady-state fluorescence spectroscopy. Thermodynamic parameters like enthalpy, entropy and free energy changes were derived by isothermal calorimetry and consequent binding parameters were compared for these heme proteins. Free energy （AG） values revealed Cu2＋ binding toward myoglobin and leghemoglobin to be specific and facile in contrast to weak binding for Hg2＋ or Cd2＋ . Time correlated single photon counting indicated significant alteration in excited state lifetimes for metal complexed myoglobin and leghemoglobin suggesting bimolecular collisions to be involved. Interestingly, none of these cations showed significant affinity for cytochrome c pointing that, presence of conserved sequences or heme group is not the only criteria for cation binding toward heme proteins, but the microenvironment of the residues or a specific folding pattern may be responsible for these differential conjugation profile. Binding of these cations may modulate the conformation and functions of these biologically important proteins.

关键词： heme proteins divalent cations fluorescence quenching isothermal calorimetry time correlated single photoncounting (TCSPC)

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Study the Hydration and the Microstructure of Cement Blended with Rice Husk Ash in Comparison with Silica Fume

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武汉理工大学学报 2010年第17期32卷 252-255,260页

作者： NGUYEN V T YE G VAN B K BUI D D Faculty of Civil Engineering and Geosciences Delft University of TechnologyP.O. Box 50482600 GADelftThe Netherlands Department of Building Materials Hanoi University of Civil EngineeringHanoi 700803Vietnam

Rice husk ask (RHA) is not a ultra-fine material as silica fume (SF),but possesses a very high specific surface area because of its porous structure. With the similar chemical composition of RHA and SF,the activity of RHA,therefore,is different from that of SF. The objective of this work is to study the hydration and the microstructure of Portland cement blended with RHA in comparison with SF. The test results show that SF refined the pore structure of cement paste better than RHA. However,the effect of RHA on cement hydration is more pronouned than that of SF for the mixture with low water to binder ratio.

关键词： hydration isothermal calorimetry mercury intrusion porosimetry (MIP) microstructure rice husk ash silica fume

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In situ X-ray diffraction and thermal analysis of LiNi0.8Co0.15Al0.05O2 synthesized via co-precipitation method

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Journal of Energy Chemistry 2018年第6期27卷 1655-1660页

作者： Na Zhang Xiaoyu Zhang Erbo Shi Shiyong Zhao Kezhu Jiang Di Wang Pengfei Wang Shaohua Guo Ping He Haoshen Zhou Center of Energy Storage Materials & Technology College of Engineering and Applied Sciences National Laboratory of Solid State Microstructures and Collaborative Innovation Center of Advanced Microstructure Nanjing University Nanjing 210093 Jiangsu China National Institute of Advanced Industrial Science and Technology (AISF) Umezono 1-1-1 Tsukuba 305-8568 Japan Zhangjiagang Guotoi Huarong New Chemical Material Co. Ltd Suzhou 215634 Jiangsu China

LiNi0.9Co0.15Al0.05O2 （NCA） material is successfully synthesized with a modified co-precipitation method,in which NH3,H2O and EDTA are used as two chelating agents. The obtained LiNi0.9Co0.15Al0.05O2 materialhas well-defined layered structure and uniform element distribution, which reveals an enhanced electro-chemical performance with a capacity retention of 97.9% after 100 cycles at 0.2 C, and reduced thermalrunaway from the isothermal calorimetry test. In situ X-ray diffraction （XRD） was employed to capturethe structural changes during the charge-discharge process. The reversible evolutions of lattice parame-ters （a, b, c, and V） further verify the structural stability.

关键词： LiNi0.9Co0.15Al0.05O2 Co-precipitation isothermal calorimetry Insitu X-ray diffraction

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HYDRATION PROCESSES OF CEMENTS BLENDED WITH LIMESTONE POWDER

HYDRATION PROCESSES OF CEMENTS BLENDED WITH LIMESTONE POWDER

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第五届水泥与混凝土国际会议

作者： Klaas van Breugel Hans S. Pietersen Faculty of Civil Engineering and Geosciences Delft University of Technology2628CNDelftThe Netherlands

Limestone powder or crushed limestone has been used in the manufacture of composite cement in France, The Netherlands and many other countries since the 1980s. This paper focuses on the kinetics of the influence of limestone powder on the hydration processes of Portland cement in the early ages using isothermal calorimetry. The temperature of isothermal calorimeter study was 20,30 and 40 C. The weight percentage of limestone in the binder were 14% and 22% and water-solid ratio was 0.33. Apparent activation energy for the cements blended with limestone powder was also determined based on experimental results and used in a numerical simulation program of cement hydration: HYMOSTRUC. Comparison between numerical simulation results and that of the experiments suggests a good correlation between the numerical hydration model and the experiments.

关键词： isothermal calorimetry apparent activation energy blended cements limestone numerical simulation

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