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Statistical study of cement additives with and without chloride on performance modification of Portland cement

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Progress in Natural science:materials International 2011年第3期21卷 246-253页

The effectiveness of cement additives with and without chloride on the fluidity and the strength development of Portland cement was compared by using statistical full factorial *** experimental results show that the cement additive containing CaCl2and Ca(NO3)2can enhance early strength of cement ***,Ca(NO3)2is less effective than CaCl2even if it is combined with other organic chemicals such as alkanolamine and *** significant difference is found between CaCl2and Ca(NO3)2influencing the fluidity and 28 d strength of *** fluidity is determined by saccharide and its interaction with *** 28 d strength enhancement is determined by *** fluidity as well as the mechanical performance of treated cement can be significantly improved by combining Ca(NO3)2with TIPA and saccharide.

关键词： Portland cement cement additive accelerator type fluidity strength development full factorial design

Formulation Design of the Multi-component Cement Additive by Using engineering Statistics

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Journal of Wuhan university of technology(materials science) 2010年第3期25卷 538-544页

作者：黄弘沈晓冬 state key laboratory of materials-oriented chemical engineering College of Material Science and EngineeringNanjing University of Technology

A novel methodology for the formulation design of the multi-component cement additive for the low early strength blend cement was presented by using engineering *** of cement additive such as triethanolamine,chloride,saccharide and a kind of divalent alcohol were simultaneously tested according to the arrangement of response surface *** models were established to express the quantitative relationship between the chemical components of cement additive and the compressive strength of treated blend *** effectiveness and the possible interactions of these four chemicals contributing to the strength development of blend cement were further explored by the pareto chart and the contour *** according the performance analysis of four chemicals,the optimized formulations were brought forward and were validated in practical trials by Turkey＇s multiple comparison.

关键词： cement additive blend cement effectiveness interaction engineering statistics

A Self-Healing Elastomer with Extremely High Toughness Achieved by Acylsemicarbazide Hydrogen Bonding and Cu2+-Neocuproine Coordination Interactions

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Chinese Journal of Polymer science 2024年第10期42卷 1425-1434页

作者： xiao-Ming An Yi-Ping Wang Tang-Song Zhu Chong Xing Xu-dong Jia Qiu-hong Zhang key laboratory of High Performance Polymer material and technology of MOE Department of Polymer Science and EngineeringSchool of Chemistry and Chemical EngineeringNanjing University state key laboratory of Coordination Chemistry Nanjing University

Elastomers with high mechanical toughness can guarantee their durability during service life. Self-healing ability, as well as recyclability, can also extend the life of materials and save the consuming cost of the materials. Many efforts have been dedicated to promoting the mechanical toughness as well as the self-healing capability of elastomers at the same time, while it remains a challenge to balance the trade-off between the above properties in one system. Herein we proposed a molecular design driven by dual interactions of acylsemicarbazide hydrogen bonding and Cu2+-neocuproine coordination simultaneously. By introducing the reversible multiple hydrogen bonds and strong coordination bonds, we successfully fabricated an extremely tough and self-healing elastomer. The elastomer can achieve an impressive top-notch toughness of 491 MJ/m3. Furthermore, it boasted rapid elastic restorability within 10 min and outstanding crack tolerance with high fracture energy（152.6kJ/m2）. Benefiting from the combination of dynamic interactions, the material was able to self-repair under 80 ℃ conveniently and could be reprocessed to restore the exceptional mechanical properties.

关键词： Hydrogen bond Metal-ligand coordination Self-healing Ultra-tough elastomer

Preparation and properties of poly(ethylene glycol)-bpoly( 3-acrylamidophenylboronic acid) glucose responsive particles and their hyaluronic acid-based microneedle patches

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Journal of Zhejiang university-science A(Applied Physics & engineering) 2024年第5期25卷 395-410页

作者： Yichuan hong Haojie YU Li WANG Xiang CHEN Di shen Yu WANG Shuning REN Yudi huang Jian YANG state key laboratory of chemical engineering College of Chemical and Biological EngineeringZhejiang UniversityHangzhou 310058China Zhejiang-Russia Joint laboratory of Photo-Electro-Magnetic Functional materials College of Chemical and Biological EngineeringZhejiang UniversityHangzhou 310058China

To overcome the pain and risk of hypoglycemia in insulin administration,glucose-responsive microneedles have been developed by researchers,which could release insulin according to the blood glucose *** designed a kind of particles by a reversible addition-fragmentation chain transfer(RAFT)method containing a phenylboronic acid group as the sensor of glucose and carrier of ***(ethylene glycol)(PEG)-2-(dodecylthio(thiocarbonyl)thio)-2-methylpropionic acid(DDMAT)was synthesized as a macromolecular RAFT agent,which was then reacted with 3-acrylamidophenylboronic acid(AAPBA)to synthesize the block copolymer ***-responsive particles loaded with insulin were prepared by self-assembly based on hydrophilic-hydrophobic *** patches loaded with glucose-responsive particles were prepared using hyaluronic acid as the *** insulin release behavior of the particles in glucose solutions of 0,100,and 400 mg/dL showed significant glucose responsiveness and good *** results of blood glucose control experiments in rats indicate that a single microneedle patch can effectively maintain normal blood glucose for over 7 h.

关键词： Diabetes Hyaluronic acid Phenylboronic acid(PBA) Glucose responsive hydrogel Microneedles

DEVELOPMENT AND APPLICATION OF A EUTROPHICATION WATER QUALITY MODEL FOR RIVER NETWORKS

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Journal of Hydrodynamics 2008年第6期20卷 719-726页

作者： ZHANG Ming-liang shen Yong-ming GUO Yakun state key laboratory of Coastal and Offshore engineering Dalian University of Technology Dalian 116023 China Department of Civil and Structural engineering The Hong Kong Polytechnic University Hong Kong China Department of engineering University of Aberdeen Aberdeen AB24 3UE UK

The Preissmann implicit scheme was used to discretize the one-dimensional Saint-Venant equations, the river-junction-fiver method was applied to resolve the hydrodynamic and water quality model for river networks, and the key issues on the model were expatiated particularly in this article. This water quality module was designed to compute time dependent concentrations of a series of constituents, which are primarily governed by the processes of advection, dispersion and chemical reactions. Based on the theory of Water Quality Analysis Simulation Program （WASP） water quality model, emphasis was given to the simulation of the biogeochemical transformations that determine the fate of nutrients, in particular, the simulation of the aquatic cycles of nitrogen and phosphorus compounds. This model also includes procedures for the determination of growth and death of phytoplankton. This hydrodynamic and water quality model was applied to calculate two river networks. As illustrated by the numerical examples, the calculated water level and discharge agree with the measured data and the simulated trends and magnitudes of water quality constituents are generally in good agreement with field observations. It is concluded that the presented model is useful in the pollutant control and in the determination of pollutant-related problems for river networks.

关键词： Preissmann implicit scheme river networks hydrodynamic model water quality model biogeochemical transformations three-step method

Cross section determination of^(27)Al(n,2n)^(26)Al reaction induced by 14-MeV neutrons uniting with D-T neutron activation and AMS techniques

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Nuclear science and Techniques 2024年第6期35卷 78-89页

作者： Xian-Lin Yang Chang-Lin Lan Yu-Ting Wei Yi Zhang Gong Jiang Bo Xie Yu Liu hong-Tao shen xiao-Jun Sun School of Nuclear science and technology Lanzhou UniversityLanzhou 730000China MOE Frontiers science Center for Rare Isotopes Lanzhou UniversityLanzhou 730000China state key laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China Guangxi key laboratory of Nuclear Physics and Nuclear technology Guangxi Normal UniversityGuilin 541004China

Aluminum is the primary structural material in nuclear engineering,and its cross section induced by 14-MeV neutrons is of great *** address the issue of insufficient accuracy for the^(27)Al(n,2n)^(26)Al reaction cross section,the activation method and accelerator mass spectrometry(AMS)technique were used to determine the^(27)Al(n,2n)^(26)Al cross section,which could be used as a D-T plasma ion temperature monitor in fusion *** the china Academy of engineering Physics,neutron activation was performed using a K-400 neutron generator produced by the T(d,n)4He ***^(26)Al∕^(27)Al isotope ratios were measured using the newly installed GYIG 1 MV AMS at the Institute of Geochemistry,Chinese Academy of *** neutron flux was monitored by measuring the activity of 92mNb produced by the 93Nb(n,2n)92mNb *** measured results were compared with available data in the experimental nuclear reaction database,and the measured values showed a reasonable degree of consistency with partially available literature *** newly acquired cross-sectional data at 12 neutron energy points through systematic measurements clarified the divergence,which has two different growth trends from the existing experimental *** obtained results are also compared with the corresponding evaluated database,and the newly calculated excitation functions with TALYS−1.95 and EMPIRE−3.2 codes,the agreement with CENDL−3.2,TENDL-2021 and EMPIRE−3.2 results are generally acceptable.A substantial improvement in the knowledge of the^(27)Al(n,2n)^(26)Al reaction excitation function was obtained in the present work,which will lay the foundation for the diagnosis of the fusion ion temperature,testing of the nuclear physics model,evaluation of nuclear data,etc.

关键词： 14-MeV neutron ^(27)Al(n,2n)^(26)Al Cross section AMS

Quantum chemical calculations of nitrogen cages N_(12)

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Chinese science Bulletin 1997年第6期42卷 462-465页

作者： QU hong, LI Qianshu and ZHU HesunSchool of chemical engineering and materials science of Beijing Institute of technology, Beijing 100081, china Stale key laboratory of Theoretical and Computational Chemistry, Jilin university, Changchun 130023, china School of chemical engineering and materials science of Beijing Institute of technology Beijing China state key laboratory of Theoretical and Computational Chemistry Jilin University Changchun China

WHILE carbon fullerenes are studied theoretically, we tend to predict if there may be some pure nitrogen molecules which possibly consist of the same geometric structures as carbon fullerenes. Experimentally Vogler et al. have obtained the intermediate absorbed at 380 nm which was assigned to N6 molecules in 1980. Some reports of ab initio calculations have appeared concerning theoretical aspects of nitrogen cage-like structures. Bliznyuk et *** the geometrical structure of N20 molecules with Ih symmetry at HF level, showing that N20 has a metastable dodecahedral geometry, with 209.34 kJ of nitrogen atoms more than that of 10N2. The N20 molecule might be a very effective high energy density

关键词： nitrogen cage ab initio calculation HEDM.

A new approach to produce polystyrene monoliths by gelation and capillary shrinkage

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science china materials 2021年第9期64卷 2272-2279页

作者： Dewang Li Yaqian Deng Jingyi Xia Zhitan Wu Tongxin Shang Pei Li Junwei Han Ying Tao Quan-hong Yang Nanoyang Group state key laboratory of chemical engineering School of chemical engineering and technology Tianjin university Tianjin 300350 China shenzhen key laboratory for Graphene-Based materials Engineering Laboratory for Functionalized Carbon MaterialsGraduate School at ShenzhenTsinghua UniversityShenzhen 518055China Joint School of National university of Singapore and Tianjin university International Campus of Tianjin UniversityFuzhou 350207China

Polymeric monoliths are of great interest in a variety of applications.A new gelation approach to produce a mechanically stable polystyrene(PS)gel directly from its microemulsion is *** produce a PS gel,the as-prepared microemulsion is first demulsified by adding selected watermiscible organic *** small PS latex particles liberated from the surfactant are assembled into a piece of bulk material at an appropriate temperature with a high degree of entanglement of the polymer *** is found that the d2 T/ηvalue is an important parameter to evaluate the gelation ability of the organic solvents and helps determine the gelation ***,PS monoliths are obtained by capillary drying and their pore structures can be effectively tuned by changing the gelation time and the amount of solvent exchanged with *** allows the controlled preparation of bulk PS artefacts with densities in the range of 0.06 to 1.14 g cm^(-3).This simple method of PS monolith production avoids the use of shaping tools or chemical templates,needs less energy,and is a promising alternative approach to design either integrated porous or compact polymer materials.

关键词： polystyrene monolith demulsification gelation capillary shrinkage

Effect of solvent on the initiation mechanism of living anionic polymerization of styrene:A computational study

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Chinese Journal of chemical engineering 2024年第5期69卷 135-142页

作者： shen Li Yin-Ning Zhou Zhong-Xin Liu Zheng-hong Luo School of chemical engineering and technology Hainan UniversityHaikou 570228China Department of chemical engineering School of Chemistry and Chemical EngineeringState Key Laboratory of Metal Matrix CompositesShanghai Jiao Tong UniversityShanghai 200240China

For living anionic polymerization(LAP),solvent has a great influence on both reaction mechanism and *** this work,by using the classical butyl lithium-styrene polymerization as a model system,the effect of solvent on the mechanism and kinetics of LAP was revealed through a strategy combining density functional theory(DFT)calculations and kinetic *** terms of mechanism,it is found that the stronger the solvent polarity,the more electrons transfer from initiator to solvent through detailed energy decomposition analysis of electrostatic interactions between initiator and solvent ***,we also found that the stronger the solvent polarity,the higher the monomer initiation energy barrier and the smaller the initiation rate ***,initiation is more favorable at lower temperatures based on the calculated results ofΔG_(TS).Finally,the kinetic characteristics in different solvents were further examined by kinetic *** is found that in benzene and n-pentane,the polymerization rate exhibits first-order ***,slow initiation and fast propagation were observed in tetrahydrofuran(THF)due to the slow free ion formation rate,leading to a deviation from first-order kinetics.

关键词： Living anionic polymerization Solvent effect Reaction kinetics Computational chemistry Mathematical modeling Kinetic modeling