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黑土、栗钙土和潮土胡敏酸分子结构的差异性分析 总被引:2,自引:0,他引:2
以北方典型的黑土、栗钙土和潮土提取的胡敏酸为研究对象,通过元素分析、傅里叶红外光谱仪及13C核磁共振仪对三者进行结构分析。不同胡敏酸的各种元素含量略有差别,各种官能团含量也不同。元素分析结果来看H/C原子比潮土最高,栗钙土次之,黑土最少;O/C的原子比三者没有明显的差别;C/N比呈现由高到低的次序分别为黑土、栗钙土、潮土。3种胡敏酸的红外光谱吸收峰相似,但吸收强度有差别,如3 352 cm-1和2 931 cm-1处潮土和栗钙土信号强度相当,黑土较低,而在2 580 cm-1处三者信号差异不明显,1 720,1 620,1 420,1 220 cm-1这4个吸收峰信号强弱均为黑土最强,栗钙土次之,潮土最弱。而从核磁共振图谱可以看出潮土结构中含有更多的多糖和蛋白质类结构单元;黑土有机质含量高,芳香化程度也较高。 相似文献
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原料乳中糊精掺假鉴别的研究 总被引:1,自引:0,他引:1
本文通过利用FOSS120红外光谱仪,对哈尔滨市区及其周边县原料乳的相关项目进行测定,建立了原料乳标准数据模型。应用此数据模型对原料乳中掺入的有害成分进行鉴别,可以对原料乳中使用糊精造假行为进行预判。 相似文献
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《Journal of Crop Improvement》2013,27(1):101-116
Abstract In pathogen population analysis of 208 Xanthomonas oryzae pv. oryzae(Xoo) strains that were assembled from different parts of India, 21 pathotypes were identified on the basis of disease reactions on near-isogenic lines (NILs) and 13 pathotypes, on rice differentials. Rice cultivars, Jyothi and IR50, which are high yielding but highly prone to bacterial blight (BB) caused by pathogen populations of Xanthomonas oryzae pv. oryzae in India, were chosen. To improve the BB resistance of these two varieties, a pyramid line, NH56, containing four R-genes, Xa4, xa5, xa13, and Xa21, was selected as the R-donor based on resistance to existing pathogen population. The four R-genes were successfully transferred to cultivars through a traditional backcross method and their presence was documented with marker-aided selection (MAS). Thirty BC4F2 plants derived from JxNH56 (cv. Jyothi) and 45 BC4F2 plants derived from IR50xNH56 (cv. IR50) had all four resistance genes (Xa4, xa5, xa13, and Xa21), which should be useful resistance donors for breeding other BB-resistant elite indica varieties. 相似文献
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Helene Fast Seefeldt Andreas Blennow Birthe Møller Jespersen Bernd Wollenweber Søren Balling Engelsen 《Journal of Cereal Science》2009
The accumulation of mixed linkage barley (1 → 3) (1 → 4)-β-d-glucan (BG) during grain filling at eight stages was studied using standard reference methods and infrared spectroscopy. Two mutant barley genotypes having higher (starch mutant lys5f) and lower (high lysine mutant lys3a) BG content than the normal control Cork were studied. The Cork and lys3a genotypes showed a linear BG accumulation throughout the grain filling to reach a maximum of approximately 6 and 4% BG (w/w) dry matter, respectively. However, lys5f mutant exhibited an exponential increase in BG synthesis to a maximum of approximately 18% BG (w/w) dry matter 30 days after flowering (DAF), seemingly compensating for a decreased synthesis of starch. 相似文献
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国内机构知识库研究综述 总被引:1,自引:0,他引:1
王胜平 《农业图书情报学刊》2008,20(11)
通过对相关研究文献的分析,对近年来机构知识库的研究做了总体回顾和总结,对机构知识库的定义、特点和功能、系统软件及其与图书馆的关系等方面的研究成果进行述评. 相似文献
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Chromium has been recognized for decades as a nutritional factor that promotes the growth of broiler chickens, but the molecular mechanism is still not clearly understood. The present study was designed to investigate the physiological and molecular mechanisms of the effects of supplemental chromium picolinate on the growth of broiler chickens. A total of 144 21-day-old Arbor Acres male broiler chicks were randomly divided into a control and an experimental group. The control group was fed a basal diet, and the experimental group was fed the same basal diet supplemented with 200 μg/kg chromium picolinate. The experiment lasted for three weeks from day 28 to 42 of the birds.. Supplementation with 200 μg/kg chromium picolinate significantly increased body weight (P < 0.05). Serum insulin levels in chickens of the experimental group were increased significantly (P < 0.05), whereas serum their glucose concentrations were decreased (P < 0.05). No significant changes were observed in serum lipid profiles in chickens fed the diet supplemented with chromium picolinate. Gene expression levels of the insulin receptor (IR) and insulin receptor substrate 1 (IRS-1), two pivotal components of the insulin signaling pathway, were also investigated using Real-time quantitative PCR. IR expression was significantly (P < 0.05) increased following chromium supplementation. Therefore, supplemental chromium picolinate had a beneficial effect on the growth of broilers. In agreement with observations in mammals, chromium might exert its effect via potentiating insulin action, and ultimately by stimulating anabolism without altering body composition in chickens. 相似文献