一次函数解法全析

江湖多险，中考路艰。 八年级上，江湖上出现了一门派“一次函数”，门中八大高手个个身手不丹，八大高手中，“取值范围”暗器一绝，防不胜防；“函数概念”功力深厚，刀法精湛；“函数表达式”轻功江湖少有人及……最令人不寒而粟的是“创新题型”，变化多端，深不可测。     

胸有万卷拿云志 家山独对寂寞心——论李贺《南园十三首》诗主题与创作心态

本文通过对李贺《南园十三首》创作背景、诗歌意境、表现意象的分析和解读，概括全诗表现的作者复杂的思想情感，疏理全诗透露出的主题信息。作为中国中唐时期的重要诗人，李贺仕后辞官之后的心态代表着一个时代文人入世与出世之间的复杂思想情感，尤其是李贺《南园十三首》所体现出来的心态更具有代表意义。     

八年级数学课堂有效提问探究

八年级数学课堂教学过程中,课堂提问环节的设置具有极其重要的现实作用,其不仅有助于引导学生的学科问题思考,而且还能在很大程度上吸引学生的学习注意力,激发学生的学科学习兴趣。本文主要结合实际教学情形,就课堂提问环节的重要性进行相应的分析探究,并提出课堂教学过程中有效提问的教学策略,以期促进八年级数学课堂教学质量的提升。     

老照片里的昔日行当

笔者在十几年老照片的收集中,发现其中有相当数量的老照片,记录了如今已消声匿迹的民风民俗、各种行当和物件等等。透过这些泛黄、甚至是残缺的老照片,我们可以穿越时空,探寻他们的生存轨迹和来龙去脉。剃头挑子一头热街头巷尾揽顾客剃头业的兴起是在满清入关之     

咏月诗话

古往今来,月是人们喜爱和称颂的事物,是纯洁和高尚的象征.许多诗人把月作为歌咏的对象.在我国最早的诗歌总集《诗经》里就有不少咏月诗,如"月出皎兮,佼人僚兮.舒窈纠兮,劳心俏兮."(《陈风·月出》)表现青年男女之间的相悦之情.《古诗十九首》里也有写得好的咏月诗,如"明月何皎皎,照我罗床帏.忧愁不能寐,揽衣起徘徊."写一个久客思家不能成寐的游子,面对皎皎月光,触动了思乡之情.被称为"建安之杰"的曹植也有"明月照高楼,流光正徘徊"(《七哀诗》)的诗句.南朝诗人谢灵运写了不少山水诗,其中《石门岩上宿》、《入华子冈是麻源第三谷》等诗也是以月为歌咏对象的.     

八年级《语文》上册中几处语病指瑕

笔在教学中发现，人教版八年级《语》上册有儿处语病，需待商榷，现列举如下：     

九十年代以来古典词学研究的八大领域

二十世纪九十年代以来,古典词学在词学史研究、词学理论研究、词学文献研究、词学个案研究、词学流派研究、词学文化研究、词学接受研究、词学学术史研究八大领域都取得了可见的成绩。这标示出我国古典词学研究的强劲态势,也预示了我国古典词学研究在本世纪前几十年间的基本走向。     

Synthetic and biological studies on a cyclopolypeptide of plant origin

Objective: A natural cyclic peptide previously isolated from Citrus medica was synthesized by coupling oftetrapep-tide units Boc-Leu-Pro-Trp-Leu-Ome and Boc-Ile-Ala-Ala-Gly-Ome after proper deprotection at carboxyl and amino terminals followed by cyclization of linear octapeptide segment.Methods: Solution phase technique was adopted for the synthesis of cyclooctapeptide--sarcodactylamide.Required tetrapeptide units were prepared by coupling of Boc-protected dipeptides viz.Boc-Leu-Pro-OH and Boc-Ile-Ala-OH with respective dipeptide methyl esters Trp-Leu-Ome and Ala-Gly-Ome.Cyclization of linear octapeptide unit was done by p-nitrophenyl ester method.The structure of synthesized cyclopolypeptide was elucidated by FTIR,1H NMR,13C NMR,FABMS spectral data and elemental analysis.The newly synthesized peptide was evaluated for dif-ferent pharmacological activities including antimicrobial,anthelmintic and cytotoxic activities.Results: Synthesis of sarcodac-tylamide was accomplished with >78% yield utilizing dicyclohexylcarbodiimide (DCC) as coupling agent.Newly synthesized peptide possessed potent cytotoxic activity against Dalton's lymphoma ascites (DLA) and Ehrlich's ascites carcinoma (EAC) cell lines,in addition to moderate anthelmintic activity against earthworms Megascoplex konkanensis,Pontoscotex corethruses and Eudrilus sp.Moreover,cyclopolypeptide displayed good antimicrobial activity against pathogenic fungi Candida albicans and Gram-negative bacteria Pseudomonas aeruginosa,in comparison to standard drugs griseofulvin and ciprofloxacin.Conclusion: Solution phase technique employing DCC and triethylamine (TEA) as base proved to be effective for the synthesis of natural cyclooctapeptide.N-methyl morpholine (NMM) was found to be a better base for the cyclization of linear octapeptide unit in comparison to TEA and pyridine.     

汉乐府民歌与《古诗十九首》比较研究

汉乐府民歌上承《诗经》《楚辞》,继承了《诗经》"感于哀乐,缘事而发"的现实主义精神,同时又吸收了《楚辞》浪漫主义特色,《古诗十九首》是我国五言古诗中最早期、最成熟的代表作品,在谋篇、遣词、表情、达意等方面对我国旧诗产生了极其深远的影响.本文从创作背景,创作内容,艺术风格、表现手法以及在诗歌史上的地位指出两者的联系与区别,进而肯定两者在推动我国诗歌发展进程中的积极作用.