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中国第三届植物化感作用学术研讨会、第八届全国杂草科学大会、联合国粮农组织——中国“水稻化感作用论坛”

作者： Xian XU,Gui-qi WANG,Cui-qin FAN,Bing-hua LI,Li-jun SU Institute of Creal and Oil Crops,Hebei Academy of Agriculture and Forestry Sciences, Shijiazhuang 050031,China

Mixing atrazine with propisochlor is one of efficacious methods that can reduce phytotoxicity of triazine herbicides on corn field succeeding *** corn field main weeds bamyardgrass and crabgrass as the treatment weeds,the experiment was conducted in greenhouse to research the optimum proportion on the mixture of atrazine and *** results showed that with soil treatment combining these two herbicides produced synergic action on controlling gramineous *** the results,when the effect of the mixture causing 90%reduction in fresh weight of bamyardgrass,the mixed ratio was choosed at 1.7-3:1 using the least dosage of the mixture,on the while,when the effect of the mixture causing 90%reduction in fresh weight of crabgrass,the mixed ratio was choosed at 1-1.8:1,by using the least dosage of the mixture.

关键词： Atrazine Propisochlor optimum proportion

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Influence of New Compound Admixture on Shotcrete Performance

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Journal of Wuhan University of Technology(Materials Science) 2017年第6期32卷 1392-1396页

作者：商岩冬郭艳培 ZHANG Wenquan ZHAO Wenbin TAN Yunzhen Department of Resources and Civil Engineering Shangdong University of Science and Technology Taian 271019 China State KeyLaboratory of Mining Disaster Prevention and Control Shangdong University of Science and Technology Qingdao 266590 China

To analyze the influence of new compound admixture on shotcrete performance, the ordinary Portland cement pr425 was used as matrix components. The optimum proportion of admixture was obtained by analyzing the influence of content on cement setting time and compressive strength. The microstructure of cement test block and the mechanism of reducing dust of composite macromolecule admixture were analyzed by scanning electron microscopy and infrared spectroscopy. It was shown that the ratio of polyacrylic acid was 0.02%. The ratio of J85 accelerator was 5%. The ratio of bentonite was 4.5% in composite admixture. The most optimal content of admixture in the slurry was 7%. The compound coagulant formed by additive together with C3A, C4AF which provided nucleation for hydration and crystallization of C3S and C3S, and played an active role to promote the activity of the mineral admixture in cement, and increased the elastic modulus of C-S-H gel and accelerated the hydration process of portland cement. Bentonite and polyacrylic acid promote the wettability, cohesiveness and workability of cement paste in the process of hydration. The formation of cement test block gel was even. The interface between the matrix phase and the aggregate phase was not obvious which ensured the matching between the matrix and the aggregate phase. The addition of bentonite formed hydrogen bonds in cement paste and improved the cohesiveness of the system. The J-85 accelerator promoted the combination of aluminate and gypsum which hindered the formation of calcium carbide around the cement particles which made cement rapid condensation. Polyacrylic acid mainly changed the strength of hydroxyl absorption peak in cement paste to improve the initial strength of cement test block. The addition of new admixtures promoted the process of cement hydration to be more thorough and affected the later strength development of concrete by affecting the formation of calcium carbonate stone.

关键词： shotcrete compound admixture optimum proportion microstructure hydration

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维普期刊数据库

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Effect of Different proportions of Wolffia on Growth of Procambarus clarkia in Two Community Scales

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Agricultural Science & Technology 2012年第7期13卷 1583-1586页

作者：季鹏飞严幸云黄成唐建清南京大学生命科学学院江苏南京210093 南京大学金陵学院江苏南京210089 江苏省淡水水产研究所江苏南京210017

[Objective] This study aimed to examine the effect of different proportions of Wolffia on the growth of Procambarus clarkia in 2 kinds of community scales. [Method] Six proportions of baits mixed by watermeal and commercial feed (0, 20%, 40%, 60%, 80%, and 100%) were designed to feed the Procambarus clarkia juveniles in 2 community scales to research the growth situation of the crayfish in different mixed baits. The growth differences between the minimal community and the larger community of crayfish in the same proportion of Wolffia were compared. [Result] The growth situations of crayfish in the 2 community scales at different proportions of watermeal were as follows: the body length was the longest in 60% watermeal group, and shortest in the pure watermeal group; the regularity was the best in the 20% watermeal group; no matter the minimal community or the larger community, there was no significant difference in the survival rate between different watermeal proportions. The growth situations of crayfish in the 2 community scales at specific proportion of watermeal were: the average body length of the minimal community was significantly greater than the larger community, and the survival rate also greater than the latter one, but the difference was not significant. [Conclusion] Considering all kinds of index such as growth, survival rate, regularity, the appropriate proportion of the baits mixed by watermeal and commercial feed is 40% to 60%; big community scale has significant inhibition on growth of crayfish, thus, there should be barriers when cultivating Procambarus clarkia juvenile.

关键词： Wolffia Minimal community Larger community Mixed feed optimum proportion

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