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61.
丁元翠方素庭徐廉竹张锋燕胡倩倩李升和任曼 《动物营养学报》2023,(4):2336-2348
本试验旨在研究苏氨酸和异亮氨酸对皖西白鹅屠宰性能、器官指数及肠道形态结构、消化酶活性、抗氧化和免疫指标的影响。选取30日龄体重相近的皖西白鹅180只,随机分为3组,每组3个重复,每个重复20只。对照组饲喂基础饲粮,苏氨酸组在基础饲粮中添加2.0 g/kg的L-苏氨酸,异亮氨酸组在基础饲粮中添加2.5 g/kg的L-异亮氨酸。试验期60 d。结果表明:1)各组之间90日龄屠宰性能和器官指数无显著差异(P>0.05)。2)异亮氨酸组60日龄十二指肠和空肠绒毛高度、隐窝深度显著或极显著高于对照组(P<0.05或P<0.01),苏氨酸组60日龄十二指肠、空肠和回肠隐窝深度及90日龄十二指肠和回肠绒毛高度显著或极显著高于对照组(P<0.05或P<0.01)。3)苏氨酸组和异亮氨酸组60、90日龄十二指肠胰蛋白酶活性极显著高于对照组(P<0.01),苏氨酸组60、90日龄十二指肠麦芽糖酶活性及90日龄空肠淀粉酶、乳糖酶活性显著或极显著高于对照组(P<0.05或P<0.01)。4)异亮氨酸组60日龄空肠总抗氧化能力显著高于对照组和苏氨酸组(P<0... 相似文献
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63.
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
64.
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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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
68.
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
69.
Both total irradiation and diffuse irradiation are necessary to building energy consumption analysis. At the most cases in China,only total irradiation is available. So some method is needed to estimate diffuse irradiation. Relationship between daily diffuse irradiation and daily total irradiation is analyzed, based on data form Beijing and Chengdu.Polynomial models for Beijing and Chengdu are established to estimate K d form K t . Validation tests show good performance of the models. Monthly means of predicted daily diffuse irradiation is not significantly different from that of the original daily diffuse irradiation. Also,the auto_correlation function of the predicted diffuse fraction, K d is coincident with that of the original K d . Beijing model can accurately predict the data of Chengdu,which is significantly different from Beijing as to the climate,so it is recommended as the general model. 相似文献
70.
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