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451.
微胶囊技术已被广泛应用于医药、农药、食品等领域,在微胶囊化过程中,微胶囊壳材料的选择对形成的微胶囊产品的性能影响起到决定性作用,重点综述以淀粉基材料作为壁材在微胶囊技术中的应用。 相似文献
452.
改性木屑对阿特拉津的吸附特性 总被引:2,自引:0,他引:2
以天然木屑为原料,通过碱化和用阳离子表面活性剂共同改性制备低成本吸附剂,通过静态吸附实验探讨了改性木屑和3种颗粒活性炭对阿特拉津(AT)的吸附行为.结果表明,改性后的木屑对AT的吸附能力明显增强,在AT质量浓度为100μg/L的务件下,改性木屑对AT的去除率可达90%.通过采用FTIR、SEM等分析手段对材料改性前后进... 相似文献
453.
Suwan1群体改良穗行选择效应研究分析 总被引:6,自引:4,他引:2
利用改良穗行选择法对热带玉米群体Suwan1改良两轮后,选用掖478、黄早四、Mo17、丹340、桂529作测验种为母本,Suwan1C0、Suwan1C1、Suwan1C2群体和墨黄9号为父本,按NCⅡ遗传交配设计组配20个测交组合,研究Suwan1改良效果。研究表明,经过两轮改良穗行选择后,Suwan1群体产量平均每轮增益6.22%;穗位变高,穗长、行粒数增加,平均每轮增益分别为5.11%、4.81%、2.25%;抽雄期变短,其他性状增益不大。产量一般配合力效应提高,但对产量特殊配合力改良效果不大。Suwan1群体与桂529有较强杂种优势,与丹340的杂种优势较弱,可用Suwan1及其自交系改良丹340等旅大红骨种质的抗病性和外观品质。 相似文献
454.
Sonja Biewer Stefan Erasmi Thomas Fricke Michael Wachendorf 《Precision Agriculture》2009,10(2):128-144
Productivity and botanical composition of legume-grass swards in rotation systems are important factors for successful arable
farming in both organic and conventional farming systems. As these attributes vary considerably within a field, a non-destructive
method of detection while doing other tasks would facilitate more targeted management of crops and nutrients in the soil–plant–animal
system. Two pot experiments were conducted to examine the potential of field spectroscopy to assess total biomass and the
proportions of legume, using binary mixtures and pure swards of grass and legumes. The spectral reflectance of swards was
measured under artificial light conditions at a sward age ranging from 21 to 70 days. Total biomass was determined by modified
partial least squares (MPLS) regression, stepwise multiple linear regression (SMLR) and the vegetation indices (VIs) simple
ratio (SR), normalized difference vegetation index (NDVI), enhanced vegetation index (EVI) and red edge position (REP). Modified
partial least squares and SMLR gave the largest R
2 values ranging from 0.85 to 0.99. Total biomass prediction by VIs resulted in R
2 values of 0.87–0.90 for swards with large leaf to stem ratios; the greatest accuracy was for EVI. For more mature and open
swards VI-based detection of biomass was not possible. The contribution of legumes to the sward could be determined at a constant
biomass level by the VIs, but this was not possible when the level of biomass varied. 相似文献
455.
Multiwalled carbon nanotubes-polymeric methyl red film modified electrode (MWNT-PMRE) was made. The electrochemical behavior of carbendazim on modified electrode was studied with Cyclic Voltammetry, Linear Sweep Voltammetry, Stable Polarization Method and Chronocoulometry. The results indicated that the electrical oxidation of carbendazim on MWNT-PMRE in H2SO4 supporting electrolyte with concentration of 0.6 mol/L was irreversible and was mainly controlled by diffusion. Some parameters of the electrochemical process were evaluated. The impacts of experiment conditions on the electrochemical behavior of carbendazim were studied. A good linearity relationship between peak current and concentration of carbendazim in the range of 2.0 × 10−7-1.0 × 10−5 mol/L was found, of which the equation was Ip(A) = −1.149 × 10−5 − 2.301c (mol/L), the correlative coefficient R = −0.9953 and detection limit was 9.0 × 10−9 mol/L. The recovery was between 90.3% and 94.7%. 相似文献
456.
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459.
Effect of high pressure processing (HPP) on buckwheat nutritional properties is investigated in this study. The results indicated that the digestion of buckwheat starches of untreated and HPP treated at room temperature (RT) showed an “internal corrosion” pattern. However, an “exocorrosion” digestion behavior was observed for the starches of HPP treated sample at 45 °C, which might be due to the formation of amylose–lipid complexes during the process as revealed by X-ray diffraction (XRD). HPP treatment at 45 °C increased the antioxidant activity of the buckwheat as measured using 1,1′-diphenyl-2-picrylhydrazylvalue (DPPH) and iron chelating capacity (ICC) compared to untreated sample (P < 0.05), which might be associated with the release of bound phenolic compounds. More importantly, this is the first study to investigate the ability of buckwheat extract for inhibiting the formation of fat droplets using a C3H10T1/2 mesenchymal stem cell line, and found that the extract of buckwheat after HPP treatment at 45 °C demonstrated significant anti-adipogenic effects. This study suggested the HPP treatment at an increased temperature (45 °C) achieved a better nutritional value of the buckwheat than both untreated and treated at RT. 相似文献
460.
为了找到一种方便、快捷且经济高效的玫瑰叶片基因组DNA提取方法,为玫瑰后期的分子生物学研究奠定良好基础,以不同品种的玫瑰幼嫩叶片为材料,分别利用CTAB法、SDS法、改良CTAB法、试剂盒法4种方法提取玫瑰基因组DNA,经过琼脂糖凝胶电泳、紫外分光光度法对所提DNA的质量和产量进行检测比较。结果表明:4种方法均可从玫瑰叶片中提取到DNA,改良CTAB法作为对常规方法的改进,在保证经济实用的前提下提取到的DNA质量最好,浓度最高;而试剂盒法作为一种快速提取植物基因组DNA的新兴方法,虽然产量略低,费用略高,但操作步骤简单,耗时短,毒害小,高效快捷。各实验室可根据实际情况选择适宜的方法。 相似文献