吉林省不同区域水稻品质特性比较及影响因素分析

吉林省不同区域的气候环境条件决定了所产稻米品质特性的差异性。为促进吉林省水稻产业发展,在构建区域种植管理模式时提供数据基础,试验选取了吉林省7个区域的共计159份稻米样本进行了品质特性的调查比较,并分析了积算温度和施氮量与品质特性间的关系。结果表明:不同区域的糙米率和精米率相差不大,整精米率、垩白粒率区域间差异则较明显。蛋白质含量和直链淀粉含量的平均值分别是8.680%和15.471%。除了弹性之外,硬度、黏度、平衡度都表现出了明显的区域间差异。精米食味值由高到低的分别是延边州、通化市、吉林市、四平市、长春市、松原市和白城市。米饭食味值由高到低的分别是延边州、通化市、松原市、吉林市、四平市、长春市和白城市。以稻花香为例进行分析的结果表明,施氮量与垩白粒率、蛋白质含量呈有意的正相关。积算温度与加工、外观、黏弹物性和食味相关品质都呈现出了有意的相关关系。

Evaluation of a Contemporary College English Listening Textbook for Second-year English Major Students at University Level

The role of textbooks,as one important channel between teachers and students,has always aroused scholars'interests,but what indeed are the roles of textbook for students and teachers? This paper aims to evaluate a listening textbook that is used by English major university students in China.Three research questions are proposed which are:(1) What are the students'per ceptions about the listening textbook? (2) What are the teachers'opinions about the listening textbook? (3) To what extent do students and teachers perceptions match? In order to answer these three research questions,questionnaires were designed for both students and teachers to obtain the data.This study is supported both qualitatively and quantitatively.The data of this research suggested that both students and teachers have found advantages of this listening textbook,which they may find helpful for their learning and teaching,but they are also not satisfied with some aspects of the textbook,which they think need further improvement.The students'and teachers'opinions to some extent have reached some agreement about the textbook,but students may not be so enthusiastic about the textbook,while the teachers may show much reliance on the text book.This study has its limitations,but it also provides some insights for teachers and textbook writers.

倒心盾翅藤中的1个新鼠李糖苷

目的研究傣药倒心盾翅藤Aspidopterys obcordate的化学成分。方法采用硅胶柱色谱、Sephadex LH-20柱色谱、ODS等色谱分离技术,对倒心盾翅藤茎醇提物的醋酸乙酯相和正丁醇相进行分离纯化,经现代波谱技术及物理常数测定等方法对所分离的化学成分进行结构鉴定。结果从倒心盾翅藤95%乙醇提取物中分离得到8个化合物,分别鉴定为3,4-二羟基苯甲酸-3-O-α-L-鼠李糖苷(1)、3,4-二羟基苯酚乙酸酯(2)、3,4-二羟基苯甲酸(3)、儿茶素(4)、β-谷甾醇(5)、胡萝卜苷(6)、cinnacasolide C(7)、尿囊素(8)。结论所有化合物均为首次从倒心盾翅藤中分离。其中,化合物1为新化合物,命名为倒心盾翅藤苷。