| 1 | Influence of shrinkage-reducing admixture on drying shrinkage and mechanical properties of high-performance concrete显示文摘High-performance concrete (HPC) has specific performance advantages over conventional concrete in strength and durability. HPC mixtures are usually produced with water/binder mass ratios (mW/mB) in the range of 0.2-0.4, so volume changes of concrete as a result of drying, chemical reactions, and temperature change cannot be avoided. For these reasons, shrinkage and cracking are frequent phenomena. It is necessary to add some types of admixture for reduction of shrinkage and cracking of HPC. This study used a shrinkage-reducing admixture (SRA) for that purpose. Concrete was prepared with two different mW/mB (0.22 and 0.40) and four different mass fractions of SRA to binder (w(SRA) = 0%, 1%, 2%, and 4%). The mineral admixtures used for concrete mixes were: 25% fly ash (FA) and 25% slag by mass of binder for the mixture with mW/mB = 0.40, and 15% silica fume (SF) and 25% FA for the mixture with mW/mB = 0.22. Tests were conducted on 24 prismatic specimens, and shrinkage strains were measured through 120 days of drying. Compressive strength, splitting strength, and static modulus of elasticity were also determined. The results show that the SRA effectively reduces some mechanical properties of HPC. The reductions in compressive strength, splitting tensile strength, and elastic modulus of the concrete were 7%-24%, 9%-19%, and 5%-12%, respectively, after 90 days, compared to concrete mixtures without SRA. SRA can also help reduce drying shrinkage of concrete. The shrinkage strains of HPC with SRA were only as high as 41% of the average free shrinkage of concrete without SRA after 120 days of drying. | Nguyen Quangphu Jiang Linhua Liu Jiaping Tian Qian Do Tienquan | 2008 | Water Science and Engineering2008，1，4： | 5 |
| 2 | Understanding divergent domestication traits from the whole-genome sequencing of swamp-and river-buffalo populations显示文摘Domesticated buffaloes have been integral to rice-paddy agro-ecosystems formillennia,yet relatively little is known about the buffalo genomics.Here,we sequenced and assembled reference genomes for both swamp and river buffaloes and we re-sequenced 230 individuals(132 swamp buffaloes and 98 river buffaloes)sampled from across Asia and Europe.Beyond the many actionable insights that our study revealed about the domestication,basic physiology and breeding of buffalo,we made the striking discovery that the divergent domestication traits between swamp and river buffaloes can be explained with recent selections of genes on social behavior,digestion metabolism,strengths and milk production. | Xier Luo Yu Zhou Bing Zhang Yi Zhang Xiaobo Wang Tong Feng Zhipeng Li Kuiqing Cui Zhiqiang Wang Chan Luo Hui Li Yanfei Deng Fenghua Lu Jianlin Han Yongwang Miao Huaming Mao Xiaoyan Yi Cheng Ai Shigang Wu Alun Li Zhichao Wu Zijun Zhuo Do Da Giang Bikash Mitra Mohammad Farhad Vahidi Shahid Mansoor Sahar Ahmed Al-Bayatti Eka Meutia Sari Neena Amatya Gorkhali Sigit Prastowo Laiba Shafique Guoyou Ye Qian Qian Baoshan Chen Deshun Shi Jue Ruan Qingyou Liu | 2020 | National Science Review2020，7，3： | 3 |
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