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81.
液相色谱-同位素质谱法鉴定蜂蜜掺假 总被引:3,自引:0,他引:3
[目的]探讨液相色谱-同位素质谱法(LC-IRMS)技术在蜂蜜掺假鉴定中的应用效果。[方法]采用LC-IRMS法检测随机抽样的62个蜂蜜样品,对蜂蜜中果糖(Fru)、葡萄糖(Glu)、二糖和三糖δ~(13)C值进行测定。[结果]由于真实蜂蜜中果糖、葡萄糖、二糖和三糖的δ~(13)C的最大值与最小值的差值小于2.1‰,果糖、葡萄糖的δ~(13)C差值(δ~(13)CFru-δ~(13)CGlu)为-1‰~1‰,且不得含有寡糖,所以该次检测样品中有48.38%的蜂蜜不合格,掺假掺杂以添加C-3植物源转化产物和淀粉糖浆为主,应加强对这类掺假的监控管理。[结论]LC-IRMS实现了蜂蜜中各种糖组分如果糖、葡萄糖、二糖和三糖等δ~(13)C的分离与分析,可进行添加了C-3糖浆的掺假鉴定,大大提高了蜂蜜掺假的检测能力。 相似文献
82.
[目的]研究配方施肥对潮土区蜜柚产量和品质的影响。[方法]采用均匀试验设计方法,在蜜柚上进行有机肥、氮肥、钾肥3因素5水平的配方施肥试验。[结果]与传统施肥习惯相比,配方施肥处理能明显提高果实的产量及改善果实的品质,而有机-无机配施的处理在提高蜜柚果实产量和改善果实品质方面的效果优于单施化肥的处理。综合产量和品质2个因素,株施有机肥料80.0 kg、化学肥料N 1.0 kg、P2O50.5 kg、K2O 1.4 kg(2号处理)的施肥配方显著提高蜜柚的产量和品质,株产达到109.87 kg。[结论]科学合理的配方施肥可提高蜜柚的产量和品质。 相似文献
83.
The aim of this study was to discriminate four commercial brands of Portuguese honeys according to their botanical origin by sensor fusion of impedance electronic tongue (e-tongue) and optical spectroscopy (UV–Vis–NIR) assisted by Principal Component Analysis (PCA) and Cluster Analysis (CA). We have also introduced a new technique for variable selection through one-dimensional clustering which proved very useful for data fusion. The results were referenced against standard sample identification by classical melissopalynology analysis. Individual analysis of each technique showed that the e-tongue clearly outperformed the optical techniques. The electronic and optical spectra were fitted to analytical models and the model coefficients were used as new variables for PCA and CA. This approach has improved honey classification by the e-tongue but not by the optical methods. Data from the three techniques was then considered simultaneously. Simple concatenation of all matrices did not improve the classification results. Multi-way PCA (MPCA) proved to be a good option for data fusion yielding 100% classification success. Finally, a variable selection method based on one-dimensional clustering was used to define two new approaches to sensor fusion, and both yielded sample clusters even better defined than using MPCA. In this work we demonstrate for the first time the feasibility of sensor fusion of electronic and optical spectroscopy data and propose a new variable selection method that improved significantly the classification of the samples through multivariate statistical analysis. 相似文献
84.
[目的]优化鲜西洋参蜜制保健酒的生产工艺。[方法]以西洋参、蜂蜜为主要原料,通过对皂苷提取工艺的优化,并辅以浓缩、配制、沉降、过滤等工艺精制成鲜西洋参蜜制保健酒。[结果]西洋参中皂苷最佳提取工艺为:在60℃时,用1倍量70%乙醇溶剂提取3h。[结论]鲜西洋参保健酒能够充分发挥西洋参中有效成分的功效,是补气养血类保健酒,且口感符合现代消费者的需求。 相似文献
85.
用蜂蜜作胡萝卜汁的稳定剂 ,可使胡萝卜汁的稳定性增强。选用羧甲基纤维素 (CMC)、果胶、琼脂和黄原胶作胡萝卜汁的稳定剂 ,其稳定效果不理想。据实验结果 ,建议在胡萝卜汁中加入蜂蜜量为 1 0 %。 相似文献
86.
电取蜂毒不利于蜜蜂群势发展和养蜂生产。电取蜂毒 3d 1次 ,连续 10次 ,可使蜂蜜减产 4 5 .6 4 %~4 9.90 % ,差异显著 (P <0 .0 5 ) ;蜂王浆产量平均降低 4 6 .17% ,差异极显著 (P <0 .0 1) ;移虫接受率平均降低31.0 5 % ,差异极显著 (P <0 .0 1) ;但对单台产浆量、饲料消耗量、蜂王有效产卵量等影响不大。连续取毒后 11d ,对蜜蜂群势的发展影响不大 ,而 2 3d后蜜蜂群势比对照组低 12 .87% ,35d后低 2 8.81% ,差异均极显著 (P <0 .0 1)。 相似文献
87.
《Wood material science & engineering》2013,8(1):24-33
Abstract Siberian larch (Larix sibirica Ledeb.) timber is suitable for many uses in the mechanical wood industry. Drying it without any decrease in value, however, is difficult and slow. The purpose of this research was to compare the drying quality of Siberian larch timber dried with three different conventional schedules taking into account the density and annual growth of wood. Five drying tests were performed. The final moisture content (MC), MC gradient, cracks, deformations (bow, crook, twist and cup) and case hardening were measured from the dried timber. The basic density particularly affected the MC, as shown in the differences regarding dried wood, with the denser wood having higher final MC and MC gradient. It was also found that large annual growth increased some deformations. Most of the measured factors were best after drying at the highest temperatures used; however, a slightly different trend was observed for bow, twist and cup. MC factors and twisting were the most problematic properties in drying according to this study. Sorting Siberian larch timber, particularly according to density, would improve the MC properties of dried timber by ensuring sufficient drying time, as economically as possible, for each timber piece. 相似文献
88.
89.
针对中国丘陵山区地形复杂、马铃薯机械化水平偏低、种植规模较小等问题,设计了一种可实现施肥、播种、开沟起垄、整形镇压一体化作业的三角链半杯勺式马铃薯精密播种机。将传统的链勺式马铃薯播种机的\"上下\"2个链轮的传动改为3个链轮的\"三角形排列\"的传动模式,增加了水平清种区,依靠重力清种,减少种薯的损伤,以及实现单粒精播的要求;将勺式取种装置改为半杯状取种装置,有效增加了取种数量,提高了取种的可靠性;通过分析计算确定了排肥系统、靴式开沟器、排种系统的工作参数,对于丘陵山区土地粘性大造成的起垄高度低、起垄不平整等问题,设计了一套开沟起垄、整形镇压装置。田间试验结果表明,当作业速度1. 9~2. 0 km/h时,粒距合格指数83. 26%,重播指数8. 36%,漏播指数8. 38%,变异系数22. 31%,垄高、垄底宽、垄面宽和垄距的稳定系数均在97%以上,性能指标符合国家标准要求。 相似文献
90.