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《物理光学》共分8章：第一章介绍了光的电磁理论；第二章介绍了两列或多列光波的叠加与分析；第三章介绍了光的干涉特性；第四章介绍了光的衍射特性；第五章介绍了光的偏振特性；第六章介绍了傅里叶光学的基本原理以及信息光学基础；第七章介绍了光纤和导波光学基础；第八章介绍了光的量子性和激光。本书在每章的后面都附有每章要掌握的重点内容，并选编了部分例题、习题和思考题，以利于学生学习，巩固基本概念和锻炼独立分析能力。

Spiders are common in daily human experience because of their biodiversity， wide distribu　tion and abundance in favorable seasons. It is unjustifiable that their significance was previously　overlooked in biological study. In western countries where Arachnology was initiated more than　a century earlier than in China， spiders used to be neglected in academic circle. In China， with　the exception of relevant papers published by Professor C. Ping and Professor Fen-chen Wang　several decades ago， arachnology remained a vacant field for a long period of time. In recent　years， owing to increasing need of biological control of insect pests in agriculture and forestry，attention has been directed to spiders with researchers gradually devoting their studies in this　field.Spiders prey essentially on insects for subsistence. Emerged about four hundred million　years ago and developed along the long evolutionary course of insects， the ancestral spider　species were terrestrial cave dwellers and sluggish in movements. With changes in natural envi-ronment and evolution of insects in their capacity of jumping and flying， spiders improved　markedly their ability in jumping and web spinning. They then developed to so-called"true spi ders"（Araneomorphae）in coincidence as insect predators. They are very specialized in possession of complicated spinnerets and well-developed silk glands secreting silk with immense　strength and elasticity. Spider silk is extraordinary in its numerous functions in pray catching，locomotion， dispersal and reproduction which are marchless in other animals. Spiders are also unique in changing pedipalps into palpal organs and in their special mode of sperm transfer. As　an arthropodian order it contains 35 000 species， uniformly as predators， thus forming a rarephenomenon in the phylogenesis of animal kingdom.Aside from their academic significance in zoological researches， spiders are highly valuable　in human productive activities as natural enemies of many agricultural and forest insect pests.In China the beneficial contributes of spiders were recognized early in ancient times. More than　two thousand years in the beginning of Han Dynasty， spiders were regarded as an augury of　good harvest. There was an old popular saying that aggregation of spiders would bring forthgood luck，which was recorded by Wu Jun， a scholar in Liang Dynasty in the period of South　Sovereighty， in his book entitled"Annotation of West Capital"as well as by Chen Yuan-long in　Qing Dynasty in his writing on"Reflection of Knowledge from Nature". Therefore， it could be　seen that our ancestors highly appreciated the beneficial effects of spiders in agriculture. Investigation conducted by scientific workers in plant protection in past ten years and more revealed　that spiders accounted for over 50 % of the total predatory natural enemies of insects in farmingareas， while in the rice fields where insecticide application was not too heavy， the population of　spiders amounted to 450 000- 3 150 000 per ha. In Hunan Province， their density in alfalfa　fields reached as high as 12 750 000 per hectare. An English scholar reported that spider population in South England grassland reached 2 265 000 per acre. It was estimated that the total　weight　of "insects destroyed by spiders in England in one year surpassed that of human population in that country. Though it is hardly possible to verify the truth of this statement， we could　positively affirm the immense capacity of spiders in destroying insect pests.The senior author of this book devoted himself in the study of taxonomy and biology of　crustaceans and leeches in his early years. Since late 1970's he turned to study spiders because　of the need of biological control of insect pests in agriculture and forestry. During this period he　published two books and some 180 papers in relation to spiders. He visited five key museums in　Germany， France and the United States， and examined type specimens and closely related　species of Chinese spiders. He found many species were identified as synonyms; and based on　his own research he gathered additional latest data including newly established taxa. It seems　obviously necessary to systematize and clarify the several hundred Chinese spider species　recorded by westerners since 1798 and a thousand and more spiders species described by Chinese in the recent two decades. His collaborators include a middle-aged professor who has　worked on spiders for years with remarkable achievements， and a young doctor who has completed his dissertation on systematics of wolf spiders and is ready to study other spider taxa.

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1.《中国国家标准汇编》是一部大型综合性国家标准全集。自1983年起，按国家标准顺序号以精装本、平装本两种装帧形式陆续分册汇编出版。本《汇编》在一定程度上反映了我国建国以来标准化事业发展的基本情况和主要成就，是各级标准化管理机构，工矿企事业单位，农林牧副渔系统，科研、设计、教学部门必不可少的工具书。2.本《汇编》收入我国正式发布的全部国家标准。各分册中如有顺序号缺号的，除特殊情况注明外，均为作废标准号或空号。3.由于本《汇编》的出版时间与新国家标准的发布时间已达到基本同步，我社将在每年出版前一年发布的新制定的国家标准，便于读者及时使用。出版的形式不变，分册号继续顺延。4.由于标准不断修订，修订信息不能在本《汇编》中得到充分和及时的反应，根据多年来读者的要求，自1995年起，在本《汇编》汇集出版前一年发布新制定的国家标准的同时，新增出版前一年发布的被修订的标准的汇编版本，视篇幅分设若干分册。这些修订标准汇编的正书名、版式形式与《中国国家标准汇编》相同，但不占总的分册号，仅在封面和书脊上注明“20××年修订-1，-2，-3，……”字样，作为本《汇编》的补充。读者配套购买则可收齐前一年制定和修订的全部国家标准。5.由于读者需求化的变化，自第201分册起，仅出版精装本。本册为第331分册，收入国家标准GB 20157-20176的最新版本。

本汇编收入了2006年制定的国家标准 48 项，其中强制性标准 1 项，推荐性标准 46 项，标准化指导性技术文件 1 项。内容涉及 电工、冶金、运输、船舶等领域。《钢铁及合金 痕量元素的测定》系列标准、《灯和灯系统的光生物安全性》、《道路交通信息采集 信息分类与编码》、《船舶与海上技术 客船低位照明 布置》等重点标准汇集在本分册。本分册为第330分册，收入国家标准GB20121～20156的最新版本。

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