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991.
为了明确通过RNA干扰技术(RNAi)获得的转基因小麦品系“Glu1Dx5RNAi”中1Dx5基因的遗传规律,以“Glu1Dx5RNAi”为供体亲本,以弱筋品种扬麦18和扬麦13为轮回亲本进行回交, 采用半籽粒SDSPAGE法检测亲本、F1、F2和BC1F1籽粒的高分子量谷蛋白亚基(HMWGS)组成。结果表明,1Dx5基因的沉默效应在杂交后代中表现为显性遗传,在F2和BC1F1世代1Dx5亚基不表达的种子数与1Dx5亚基表达的种子数的比例分别符合13∶3和3∶1的分离比例,说明转小RNA基因导致1Dx5基因沉默是单基因显性遗传。对转基因小麦“Glu1Dx5RNAi”及其受体品种Bobwhite进行品质测试表明,Glu1Dx5RNAi蛋白质含量(13.28%)比转化受体Bobwhite(12.83%)高0.45个百分点,硬度指数、微量SDS沉降值比受体品种分别降低3.13和3.7 mL。1Dx5基因沉默对弱筋小麦育种可能会有一定的利用价值。 相似文献
992.
993.
A coking plant extended many times, and its capacity of the cooling water system is not match with it, the consumption of new water is much more than that used by others in the same industry. The water system renovation is addressed for an extended coking plant. The installation of two 600 m3/h cooling towers and restoration the existing two cooling towers are to promote the cooling capacity so that the amount of discharge and feed could be reduced. At the same time, the pipe net for waste water reutilisation is installed, by which part of the waste water is reused as supplement water for quenching hot coke and the other was piped to ironworks for reuse. With the field test, the water consumption per ton of coke production is cut down from 9.03 m3 to 3.21 m3. And the annual water saving is more than 6×106 m3. Furthermore, the electric consumption is reduced by 2×106 kWh and about 3×106 yuan of annual running cost is saved. 相似文献
994.
Medical images usually contain much noise which affects the edge detection accuracy. Focusing on this problem, based on the edge detection operator in mathematical morphology, an improved edge detection algorithm is presented by combining the features of the multi structure elements and the multi scale edge detection algorithm. The algorithm performs opening and closing operations on the data with the alternative sequence filters and the structure elements. The weighting operation is applied with different weight coefficients for horizontal, vertical and diagonal directions, while the edge detection operator with dilation type is calculated to obtain the improved edge detection algorithm. The steps of the algorithm are described. The algorithm is used to extract the edge of MRI image as well as the image of Lena. The experimental results indicate the algorithm can considerably improve the edge resolution of the traditional morphological edge detection methods and is practical. 相似文献
995.
Development model of emulsified oil jet and micro-explosion properties of water drops are analyzed,cavitation effect can change the jet atomizing angle,therefore,an important guideline to describe oil jet atomization is atomizing angle. Absolute diesel fuel and different moisture content emulsified diesel fuels are researched by high-speed camera system from the experiment for studying the atomizing properties of water drops when high-voltage impulse injects the gas medium. The theory and experimental results show that lots of water drops of emulsified oil reduce jet dynamic strength when the jet unloads,so it has stronger dispersed properties. Emulsified diesel fuel can spray more capacity than absolute diesel fuel,the width of jet is greater and the spraying atomizing angle increases. When the moisture percent of emulsified oil is 10%,the atomizing angle can get to the maximum. 相似文献
996.
997.
蔷薇科甜茶加工应用研究进展 总被引:1,自引:0,他引:1
蔷薇科甜茶营养丰富,含有甜茶甙、多酚、黄酮等多种活性物质。总结了蔷薇科甜茶的加工应用状况,为蔷薇科甜茶的进一步加工应用和市场开发提供参考。 相似文献
998.
R. Inclán C. Uribe D. De La Torre D. M. Sánchez M. A. Clavero A. M. Fernández R. Morante A. Cardeña M. Fernández A. Rubio 《European Journal of Forest Research》2010,129(1):93-100
Understanding the spatial and temporal variation in soil respiration within small geographic areas is essential to accurately assess the carbon budget on a global scale. In this study, we investigated the factors controlling soil respiration in an altitudinal gradient in a southern Mediterranean mixed pine–oak forest ecosystem in the north face of the Sierra de Guadarrama in Spain. Soil respiration was measured in five Pinus sylvestris L. plots over a period of 1 year by means of a closed dynamic system (LI-COR 6400). Soil temperature and water content were measured at the same time as soil respiration. Other soil physico-chemical and microbiological properties were measured during the study. Measured soil respiration ranged from 6.8 to 1.4 μmol m?2 s?1, showing the highest values at plots situated at higher elevation. Q 10 values ranged between 1.30 and 2.04, while R 10 values ranged between 2.0 and 3.6. The results indicate that the seasonal variation of soil respiration was mainly controlled by soil temperature and moisture. Among sites, soil carbon and nitrogen stocks regulate soil respiration in addition to soil temperature and moisture. Our results suggest that application of standard models to estimate soil respiration for small geographic areas may not be adequate unless other factors are considered in addition to soil temperature. 相似文献
999.
Zanetti E De Marchi M Dalvit C Molette C Remignon H Cassandro M 《British poultry science》2010,51(5):629-634
1. An experiment involving 60 male chickens reared in an organic production system was carried out in order to investigate carcase characteristics and qualitative meat traits of three slow-growing Italian local breeds of chicken (Ermellinata, Padovana and Pepoi). 2. Chicks were randomly selected at hatch, raised together under the same conditions, slaughtered at 190 d of age, dissected for carcase traits, and meat (breast and thigh) stored for subsequent analysis of quality parameters. 3. Ermellinata (EA) chickens were significantly different from Padovana (PA) and Pepoi (PI) chickens for live, carcase and thigh weights. Breeds were also different for breast muscle protein content (EA > PI and PA), shear force (PA < EA and PI) and cooking loss (PI > PA and EA) values. 4. The CIE system values of lightness (L*), redness (a*), and yellowness (b*) evidenced a distinctive darker meat and lighter skin colour of PA breast meat. 5. Polyunsaturated fatty acids composition of breast meat was similar among the analysed breeds. EA had significantly higher saturated but significantly lower monounsaturated fatty acid contents than the other two breeds. 相似文献
1000.
灵芝多糖提取纯化及抗氧化研究 总被引:1,自引:0,他引:1
采用Sevag法和HCl法研究了灵芝多糖纯化过程中的去蛋白方法,通过不同体积分数乙醇分级醇沉多糖的沉淀量探索了不同来源灵芝多糖的抗氧化性。结果表明,Sevag法和HCl法都可除去灵芝多糖提取液中的杂蛋白,但两种方法的去蛋白效果和多糖损失率差异明显。Sevag法的蛋白去除率(82.41%)高于HCl法(41.60%);同时其多糖损失率(36.03%)也比HCl法(14.41%)大;乙醇分级沉淀灵芝多糖研究表明,40%、65%和80%乙醇沉淀灵芝多糖量比例为0.41∶0.42∶0.17;多糖浓度与清除羟基自由基和超氧阴离子的能力呈正相关,且分级沉淀的多糖在等浓度条件下其抗氧化性也显示出明显差异,总的清除能力为80%乙醇40%乙醇65%乙醇。 相似文献