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     

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.     

八年级（上）第一单元教案

人类的历史就是一部战争的历史。屈辱的战争。我们不应该忘记；和平的阳光。我们更应该珍惜。解读历史，审视现在，展望未来。世界应早日铸剑为犁……本单元选文以叙事类文章为主。有新闻、小说、通讯、书信等文体。有的谴责非正义战争的残酷．有的记叙正义战争的胜利：作者既有“指点江山”的一代伟人，也有“激扬文字”的中外著名作家。学习本单元，要求：1．把握课文内容；2．评价人物形象；3．品味特色语言；4．体验特定情景与人物心情。     

指导背诵例谈

师：同学们，在大屏幕上，老师出示了三段文字，你分别感受到了怎样的声音呢？     

是“如厕”还是“入厕”

河北省赵海霞老师就人教版第八册第二课《古诗两首》中《惠崇春江晚景》一诗的“晚”提出：从本诗中的四句所涉及到的景物——桃花开、江水暖、鸭先知、蒌蒿满地芦芽短、河豚欲上时，均属早春景色，并非晚春，诗题中的“晚”应如何理解?     

感动着《一个中国孩子的呼声》——《一个中国孩子的呼声》教学片断与评析

教材简析 《一个中国孩子的呼声》选自人教版教材小学语文第八册。是篇精读课文，属书信体文章，课文内容是一个因失去了父亲而悲愤的、对和平无比渴望的中国孩子写给当时的联合国秘书长加利的一封信，信中缅怀父亲——一个为维护肚界和平而献出宝贵生命的英雄，并代表中国孩子呼吁国际社会：一致行动，维护和平，制止战争。     

Dijkstra算法与A~*算法研究

对于单源点最短路径问题可用Dijkstra算法进行实现,对两点间(单源点、单目的点)最短路径问题则用A~*算法实现。重点对A~*算法的实现作了细致的讨论,并用A~*算法解决了八数码问题。