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几种外源激素对韭葱种子发芽的影响 总被引:10,自引:0,他引:10
本试验以韭葱为材料,用几种不同浓度的外源激素:吲哚乙酸(IAA)、萘乙酸(NAA)和赤霉素(GA3)处理,结果表明,除100 mg/L的NAA外,各种处理对韭葱种子的发芽势和发芽率都有一定程度的提高,其中以50 mg/L的GA3处理效果最佳. 相似文献
74.
According to the structural characteristics of bridge engineering, the mix optimization design method of bridge fair-faced concrete was presented, and C30~C50 concrete with high cohesion and package, outstanding fluidity and excellent mechanical properties were prepared. Through the test of air content of fresh concrete, micro hardness and micro structure in different parts of hardened concrete specimens, effects of viscosity-modifying admixtures on homogeneity of concrete were discussed. The results showed that the composition of bridge fair-faced concrete were relatively homogeneous, and the microstructure were relatively dense. When C30 concrete mixed with 5 × 10 -5 cellulose ether or 6% silica fume (mass fraction of cementitious material), air content of fresh concrete were less than 2%, and slurry viscosity values were between 1 900 and 2 000 MPa·s. Also, the micro hardness values in different parts of hardened concrete specimens were closed. The results were applied in practical bridge engineering, which generally meets the apparent quality requirements of bridge fair faced concrete. 相似文献
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This paper presents the principle of high-pass-absolute-value demodulation tcchnigue which is applied with spectrum analysis to investigate the vibration and noise produced by the C61 32 Lathe. The main noise sourse is found out and some reliable data are provided to decrease the noise and vibration and to improve the dynamic performence of the c6132 Lathe. 相似文献
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The exact three di me nsional temperatu re distribution and thermal analysiS to inte-grated circuit substrates have been presen ted by means of numerical method of a fin ite difference.Thismethed.which will overcome the di fficuItv of mathematical deduction mav be consltieredas an analytical way aided by com puters for thermal design of electron ic compon ents. 相似文献
79.
Wen Guangjun Xie Fuzhen Wang Ding 《保鲜与加工》1992,(1):134-138
The holographic three wavefront interferometer is used to measure large optical path difference. This method is proved to be practical through the measurement of the deformation -Voltage Curve of piezocrystal. 相似文献
80.
The mathematical relationship for assessing total energy consumption within a material life cycle is presented in this paper. According to the relationship,the procedure rationality of recycling waste may be assessed quantitatively. 相似文献