中国油菜单产增长要素贡献率分析

运用因子分析技术将影响中国油菜单产的众多因素综合为物质费用、劳动力、政策制度和结构与灾害四大因素,并利用Cobb-Douglas型生产函数模型分别测算了四大因素在中国油菜单产增长中的贡献率。根据1990～2004年间的数据计算,物质费用对中国油菜单产增长的贡献率最大,其次是劳动力和政策制度,而同期结构与灾害因子对单产有负向影响。     

重读蒲柏的英雄滑稽诗《夺发记》

亚历山大.蒲柏是18世纪最伟大的诗人,作为英国启蒙时代的代表,推崇理性主义。十九世纪,他的名声一度跌落;20世纪以来,他因其诗歌的高度艺术性重振声名。尤其是《夺发记》,成为戏仿史诗的经典,为诗歌爱好者提供了解史诗和传统诗歌的上乘之作。     

亚麻织物绳状煮练纵向条纹产生的原因及解决

本文对亚麻织物绳状煮练纵向条纹产生的原因进行了分析,并提出了解决纵向条纹的方法,即煮练时加入高效煮练助剂,丝光对减轻纵向条纹也是有效的。     

Effect of Brussels sprouts and inulin/rape seed cake on the sensory profile of pork M. longissimus dorsi

The objective of the present study was to evaluate the influence of two diets containing either Brussels sprouts or inulin/rape seed cake, compared with a standard diet (control) for slaughter pigs on flavour and odour attributes and sensory profile of cooked pork. Three weeks prior to slaughter 24 female pigs were allocated to three diets: (1) a standard grower-finishing diet (control) for slaughter pigs containing barley, wheat and soy-bean meal, (2) the control diet containing 11 energy percent Brussels sprouts and (3) a diet containing 25% inulin and 55% rape seed cake. The odour and flavour of the cooked meat from inulin/rape seed cake-fed pigs differed significantly from the other two diets, showing reduced meat odour, increased pig and acrid odour, increased pig flavour, reduced fresh flavour and total impression. Meat from the Brussels sprouts-fed pigs deviated only slightly from the control-fed pigs.     

Analysis of saturated free fatty acids from pollen by HPLC with fluorescence detection

A sensitive method for the determination of free fatty acids using 2‐(2‐(anthracen‐10‐yl)‐1H‐naphtho[2,3‐d]imidazol‐1‐yl) ethyl‐p‐toluenesulfonate (ANITS) as tagging reagent with fluorescence detection has been developed. ANITS could easily and quickly label fatty acids in the presence of the K₂CO₃ catalyst at 90 °C for 40 min in N,N‐dimethylformamide solvent. From the extracts of rape bee pollen samples, 20 free fatty acids were sensitively determined. Fatty acid derivatives were separated on a reversed‐phase Eclipse XDB‐C₈ column by HPLC in conjunction with gradient elution. The corresponding derivatives were identified by post‐column APCI/MS in positive‐ion detection mode. ANITS‐fatty acid derivatives gave an intense molecular ion peak at m/z [M+H]⁺; with MS/MS analysis, the collision‐induced dissociation spectra of m/z [M+H]⁺ produced the specific fragment ions at m/z [M–345]⁺ and m/z 345.0 (here, m/z 345 is the core structural moiety of the ANITS molecule). The fluorescence excitation and emission wavelengths of the derivatives were λ_ex = 250 nm and λ_em = 512 nm, respectively. Linear correlation coefficients for all fatty acid derivatives are >0.9999. Detection limits, at a signal‐to‐noise ratio of 3 : 1, are 24.76–98.79 fmol for the labeled fatty acids.     

不同氮素水平油菜冠层反射光谱特征研究

2002～2003年油菜生长季节,在浙江大学实验农场设置了4个品种、3个供氮水平处理、3个重复的油菜田间小区试验,测定了不同发育时期的冠层光谱反射率及对应叶片、茎以及角果的鲜重和干重。结果表明：不同供氮水平的油菜冠层和叶片光谱差异明显,冠层光谱反射率随发育期推移,开花前在可见光范围逐渐降低、在近红外区域逐渐增大,开花后在可见光范围逐渐增大,在近红外区域逐渐降低。不同供氮水平的油菜冠层光谱差异明显,4个品种的油菜具有相似的变化规律,在近红外表现尤其明显,随着供氮水平的增加,光谱反射率明显升高;而在可见光波段处,随供氮水平提高,反射率反而降低。前期随发育期推移,NDVI和RVI都逐渐增大,在4月22日达到最大,其中N2和N3在4月14日受开花影响,NDVI和RVI有所降低。4月22日以后,由于后期叶片衰老变黄,NDVI和RVI都逐渐减小。     

油菜蜂花粉中粗黄酮提取物成分分析

为了明晰油菜蜂花粉中黄酮类物质的组成及脉冲电场辅助提取效果,试验采用TLC—DPPH和HPLC等方法对油菜蜂花粉的乙醇提取物及其酸解产物进行了详细的组分分析。结果表明,油菜蜂花粉的乙醇提取物中槲皮素和山奈酚因含量过低而未能检出,但该提取物经酸水解后,则会形成大量槲皮素和山奈酚,故可初步推断油菜蜂花粉中的黄酮类化合物主要以黄酮苷的形式存在。未经脉冲电场破壁处理的蜂花粉乙醇提取物的酸解物中,槲皮素含量为764.39μg/g,山奈酚含量为1 647.97μg/g,而经破壁处理后,槲皮素含量达867.93μg/g,对比提高了13.55%,山奈酚含量达1 924.03μg/g,对比提高了16.75%。该结果充分证明了脉冲电场预处理对油菜蜂花粉细胞具有良好的破壁效果。     

湖北省油菜田灾害性杂草高效防控技术研究进展

综述了湖北省油菜田杂草及种子库种类组成和特征、油菜田主要灾害性杂草的发生危害规律以及高效化学防除和生态防除技术。探讨了建立生态调控与化学除草相结合的农田杂草可持续治理技术体系的研究前景。     

氮离子注入油菜M1代的生物学效应

研究了氮离子(N+)注入油菜干种子引发的当代生物学效应.结果表明N+在3.2×1016-4.6×1016/cm2注量范围内处理不影响油菜种子发芽;以3.9×1016/cm2注量处理可提高种子出苗率和成苗率;适当注量处理可促进苗期株高、叶片数和单株鲜重的增加,对成株期叶片数、茎粗、最大叶片长和宽等生物性状以及一次有效分枝数、全株总角果数和单株产量等经济性状均具有明显的生长刺激效应.同时,离子束处理区表现出广泛的变异,变异株率达到3.2%.