沉默期理论的再认识

本文认为,沉默期不仅存在于一语习得过程中,在外语学习过程中也普遍存在,外语语言规则的习得存在沉默期。英语教师应该正确认识和区分学生学习某一语言规则时出现的沉默期现象与课堂中的沉默现象,并设法增加适当的可理解输入,使学习者对该语言规则的“沉默期”缩短。     

阅读——图书馆生生不息的有机体 ——兼评让·马里·古勒莫的《图书馆之恋》

《图书馆之恋》记录作者从识字阅读开始与图书馆结下的深厚情缘,让图书馆人深刻体会读者对图书馆的那份深情。“阅读”作为图书馆存在并得以生生不息发展的原动力,现在乃至将来仍然是图书馆赖以传承和变革的出发点和落脚点。《图书馆之恋》可以让我们从读者的角度更客观、理性地认识和理解图书馆,从而更好地面对读者,思考阅读在图书馆发展的未来。     

绿春萝芙木资源薄层色谱鉴别

根据形态学特征对绿春县萝芙木(Rauvolfia L.)资源进行鉴定,同时采用薄层色谱法进行色谱鉴别.结果表明,绿春产萝芙木分别为萝芙木Rauvolfia vericillata(Lour.)Bail.和云南萝芙木Rauvolfia yunnanensisTsiang,两者色谱特征差异明显,但两者均含有药用成份利血平(reserpine)和育亨宾(yohimbine),开发时应综合利用.     

野生和栽培马齿苋黄酮含量的比较研究

采用微波辅助乙醇浸提的方法提取马齿苋黄酮,并通过正交试验确定了最佳提取条件。结果表明,微波辅助提取的影响因素顺序为：料液比〉微波处理时间〉乙醇浓度〉微波强度;马齿苋黄酮微波辅助乙醇浸提的最佳条件为：料液比1：50（g/ml）、微波处理时间120s、乙醇浓度70%、微波强度为中高火档（648W）。提取得到野生型和栽培型马齿苋黄酮含量分别为：5.432%和5.506%。     

L~ψ空间中的K-泛函与光滑模

讨论Lψ空间中K -泛函与光滑模的等价性 ,得到了Lψ空间中的函数及其导数对应的K -泛函与光滑模之间的等价性定理 ,推广了文 [2 ]的结果。     

新发现绿野堂《歧路灯》抄本刍议

新见绿野堂《歧路灯》抄本20卷,105回,除卷首有一段交代作者李海观生平、堂号、诗作的文字外,与上图抄本相比还有明显的增删,尤以第八回、第九回和第十回中较为突出。在语言上绿野堂抄本更多地使用书面词语,富于文采。绿野堂抄本应和安定筱斋抄本、洛阳民国石印本等一样,同属于国图抄本系统。     

Cloning and characterization of a glucose 6-phosphate/phosphate translocator from Oryza sativa

INTRODUCTIONNongreenplastidsofheterotrophictissuesarecarbohydrate importingorganellesand ,inthecaseofamyloplastsofstoragetissues,thesiteofstarchsynthesis.Investigationofwholetissuesfromavarietyofstarchsynthesizingcropplantsindicatedthathexoseunitswereimpo…     

Characterization of enhancer trap and gene trap harboring Ac/Ds transposon in transgenic rice

INTRODUCTIONAfterthewholericegenomewassequencedsuccessfully,moreandmoregenescanbepredictedwithdifferentsoftwaresandannotationsystem.However,thefunctionsofpredictedgeneshavetobefurtheridentifiedbybiologicalanalysis.Oneofthemostpowerfulmethodsassigningfunctiontogeneisthroughinsertionmutagenesiswithtrans-posableelementasDNAsequencetag.Ac/Dstrans-posonsystemhasbecomeaverypopulartoolforgenetaggingandfunctionalgenomicsinvariousplantspecies(Altmannetal.,1995;Chinetal.,1999;Enokietal.,1999;Gre…     

Effects of light and temperature conditions on flowering in Mat Rush

The effects of photoperiod and light intensity on flowering in Mat Rush cv. Gangshan 3 were studied. The results showed that treatments with longer day length stimulated flowering significantly and increased stem flowering percentage (SFP). Plants treated with low light intensity at early stage had substantially reduced florets per cyme, SFP, tillers per plant and stem length. At middle and late stage, low light intensity significantly reduced SFP. The principal climatic factors affecting SFP were as follows: mean temperatures (MT) of the third ten-day period (TDP) in December and of the second TDP in February, actual sunlight hours (SH) of the third TDP in February and precipitation of the third TDP in March. A nonlinear simulation model for SFP was established with experimental results and corresponding climatic data (see Eq. (2)). Simulation by the above equation yielded values the same as those observed from 1992 to 2000, indicating its accuracy in describing the relationship between flowering and light and temperature conditions. The interaction between vernalization and SH is also discussed in this paper. Project (No. 981105) supported by the Ningbo City Science Foundation, China     

景天三七中总黄酮提取条件和含量分析

目的：研究不同提取溶剂对景天三七中总黄酮的含量影响及最佳提取条件下总黄酮的含量。方法：采用盐酸一镁粉法和醋酸铅法对景天三七中总黄酮进行检识,并用不同溶剂对景天三七中总黄酮进行了提取,以分光光度法测定总黄酮含量,以芦丁为标准品,以10％AI（NO2）3-5％NaNO2为显色剂,在508nm波长处进行测定。结果：检识试验证明景天三七中含有黄酮类物质,且最佳提取溶剂为80％乙醇（P〈0．05）。在此提取条件下,测得景天三七中总黄酮的含量为18．39mg·g～,RSD为2．2％（n=5）。总黄酮测定线性范围为15．20-45．60beg·mL^-1。（r=0．9997）,平均回收率为95．74％,RSD为0．98％（n=6）。结论：景天三七中黄酮类物质的最佳提取溶剂为80％乙醇。本法准确可靠,重现性好,结果稳定,适合于景天三七中总黄酮含量分析。