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191.
Yue Choong Kog 《Geomechanics and Geoengineering》2019,14(1):1-11
The development of negative skin friction on circular piles in a consolidating layered soil is investigated by an elasto-plastic load transfer theory which accounts for slippage of the soil. The elastic load transfer theory is premised on the compatibility condition that the vertical displacement of the ‘pile’ is equal to the summation of the vertical displacement of the layered soil due to the consolidation of the upper soil layer and the vertical displacement in the ‘soil layers’ along the pile’s centroidal axis caused by a system of pile-soil interactive forces. Slippage of the soil is accounted for by imposing the shear strength of the clay layer as the limit of the pile-soil interface shear stress. The saturated upper clay is consolidating under a uniform surcharge in accordance with Terzaghi’s one-dimensional consolidation theory. The validity of the proposed solution is confirmed by comparison with field measurements. Extensive parametric studies with regard to the effect of pile-soil slip on pile behaviour are presented. 相似文献
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This study was conducted to compare lipid and fatty acid composition of cod,haddock and halibut.Three groups of cod(276 g±61 g),haddock(538 g±83 g)and halibut(3704 g±221 g)were maintained with commercial feeds mainly based on fish meal and marine fish oil for 12 weeks prior to sampling.The fatty acid compositions of muscle and liver were determined by GC/FID after derivatization of extracted lipids into fatty acid methyl esters(FAME).Lipids were also fractionated into neutral and polar lipids using Waters silica Sep-Pak(R).The phospholipid fraction was further separated by high-performance thin-layer chromatography(HPTLC)and the FAME profile was obtained.Results of the present study showed that cod and haddock were lean fish and their total muscle lipid contents were 0.8% and 0.7%,respectively,with phospholipid constituting 83.6% and 87.5% of the total muscle lipid,respectively.Halibut was a medium-fat fish and its muscle lipid content was 8%,with 84% of the total muscle lipid being neutral lipid.Total liver lipid contents of cod,haddock and halibut were 36.9%,67.2% and 30.7%,respectively,of which the neutral lipids accounted for the major fraction(88.1%-97.1%).Polyunsaturated fatty acids were the most abundant in cod and haddock muscle neutral lipid.Monounsaturated fatty acid level was the highest in halibut muscle neutral lipid.Fatty acid compositions of phospholipid were relatively constant.In summary,the liver of cod and haddock as lean fish was the main lipid reserve organ,and structural phospholipid is the major lipid form in flesh.However,as a medium-fat fish,halibut stored lipid in both their liver and muscle. 相似文献
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195.
固定化酶在高浓度有机废水处理中的应用 总被引:11,自引:2,他引:9
选用硅胶、活性炭、大孔树脂三种载体,在一定条件下用物理吸附法固定蛋白酶,三种载体固定的蛋白酶对含高浓度蛋白质的淀粉黄浆废水进行水解实验,确定水解最佳的pH值范围,并在此条件下研究三种不同载体上固定化酶的活性及其水解规律。结果表明:大孔树脂对蛋白酶的固定效果良好,并对含高浓度蛋白质的废水处理效果最好,其最佳反应pH值为5.5,反应进行0.5 h时酶的催化效果最好,氨基酸产生速度达到30.82 mg/min,且在3h后该速度仅减少3.74 mg/min;6 h时对蛋白质的去除率达到39.93%。 相似文献
196.
Ustadi K. Y. Kim S. M. Kim 《中国海洋大学学报(英文版)》2005,4(3):198-204
The protease inhibitor was purified from five different fish eggs. The molecular weights of Pacific herring, chum salmon, pond smelt, glassfish, and Alaska pollock egg protease inhibitors were 120, 89, 84.5, 17, and 16.8kDa, respectively. The specific inhibitory activity of glassfish egg protease inhibitor was the highest followed by those of Pacific herring and Alaska pollock in order. The specific inhibitory activity and purity of glassfish egg protease inhibitor were 19.70 U mg^- 1 protein and 164.70 folds of purification, respectively. Glassfish egg protease inhibitor was reasonably stable at 50 - 65℃ and pH 8, which was more stable at high temperature and pH than protease inhibitors from the other fish species. Glassfish egg protease inhibitor was noncompetitive with inhibitor constant (Ki) of 4.44 nmol L^-1 相似文献
197.
用主振荡型( P O P)方法分析了热带洋区月平均海表温度异常( S S T A)。结果表明,最重要的 4 个传播型 P O P对与 El Nino/ La Nina 事件关系密切,说明这类事件具有复杂的时空结构。在此基础上,给出了一个能定量地综合多个传播型 P O P对作用的 P O P中性预测方案。非独立样本和独立样本试验表明,它具有 4 个月的预测时效,且其预测能力在 S S T 强异常的 El Nino、 La Nina 事件阶段强于弱异常的非 El Nino/ La Nina 事件阶段。 相似文献
198.
Development of the Convective Boundary Layer Capping with a Thick Neutral Layer in Badanjilin: Observations and Simulations 总被引:1,自引:0,他引:1
In this study,the development of a convective boundary layer (CBL) in the Badanjilin region was investigated by comparing the observation data of two cases.A deep neutral layer capped a CBL that occurred on 30 August 2009.This case was divided into five sublayers from the surface to higher atmospheric elevations:surface layer,mixed layer,inversion layer,neutral layer,and sub-inversion layer.The development process of the CBL was divided into three stages:S1,S2,and S3.This case was quite different from the development of the three-layer CBL observed on 31 August 2009 because the mixed layer of the five-layer CBL (CBL5) eroded the neutral layer during S2.The specific initial structure of the CBL5 was correlated to the synoptic background of atmosphere during nighttime.The three-stage development process of the CBL5 was confirmed by six simulations using National Center for Atmospheric Research (USA) large-eddy simulation (NCAR-LES),and some of its characteristics are presented in detail. 相似文献
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