粮食储藏过程中黄曲霉毒素检测与去除研究进展

简述了黄曲霉毒素的理化性质,重点介绍了粮食在储藏过程中黄曲霉毒素的检测方法并比较了各种方法的优缺点,同时论述了黄曲霉毒素的去除方法,希望为黄曲霉毒素的有效防控提供一定的借鉴。

枣离体幼胚发育影响因素的研究

【目的】为延长败育前枣幼胚的发育程度,提高枣幼胚挽救效率。【方法】以枣品种‘冷白玉’、‘六月鲜’、‘襄汾圆枣’胚龄20~40 d幼胚为试材,在明确枣幼胚发育状况的基础上,对影响离体幼胚发育的基因型、适宜取样的最小胚龄、植物生长调节物质进行了研究。【结果】‘冷白玉’和‘六月鲜’枣20~40 d胚龄的幼胚发育相对一致,而‘襄汾圆枣’幼胚发育快于这2个品种;3个品种幼胚成胚难易程度依次为‘冷白玉’、‘襄汾圆枣’、‘六月鲜’;不同枣品种、不同胚龄对植物生长调节物质的响应不同;适宜3个品种幼胚挽救取样的最小取样胚龄为30 d,‘冷白玉’、‘襄汾圆枣’、‘六月鲜’成胚率分别为56.82%、54.17%、52.53%。【结论】胚龄对枣离体幼胚生长发育的影响最大,按作用大小排序依次为胚龄>品种>植物生长调节物质种类>植物生长调节物质浓度。

Expanders, Group Extensions, Hadamard Manifolds and Certain Banach Spaces

In this note,we prove that expanders cannot be coarsely embedded into group extensions of sequences of groups which are coarsely embeddable into Hardamad manifolds and certain Banach spaces due to the similar concentration theorems.

A Class of Metric Spaces Which Do Not Coarsely Contain Expanders

In this paper, a class of metric spaces which include Hilbert spaces and Hadamard manifolds are defined. And the expanders cannot be coarsely embedded into this class of metric spaces are proved.