Azimuth space-variant properties of BiSAR with nonequal velocities

Bistatic SAR possesses characteristic of the azimuth space-variant when the velocities of transmitter and receiver are not equal. The geometric model of BiSAR with the parallel trajectories and the nonequal platform velocities is presented. Analyzing the motion relationship of transmitter and receiver, the formula of azimuth spacevariant is derived in time domain. Via Taylor polynomial expansions, the azimuth space-variant is factorized by four terms： zero-order, first-order, second-order, and third-order term. And, their impacts on impulse response are illuminated. Some characteristics about azimuth space-variant of airborne BiSAR case are exhibited by simulation experiments, and these simulated results are coincident with the formulae of azimuth space-variant.     

信息时代下现代汉语的功能变体——网络语言初探

随着信息时代中网络交流的日益普及,一种全新的语言模式--网络语言,正悄然而真切地进入并影响着我们的生活.网络语言,是现代汉语在信息时代下的功能变体,兼具书面语和口语的语体特征,其语体特征和语体功能决定了我们应该因循社会发展规律,逐步引导、逐步规范,使传统现代汉语与网络语言互相取长补短,共同发展.     

网络语言的特征

计算机网络的兴起和发展丰富和改变了人们的交流方式。网民在网络这个新的载体上所使用的语言是一种语言变体,具有其鲜明的特征。本文从社会语言学的角度,基于网络聊天室,网络文章等语言的使用状况,分析网络语言的主要特征。     

藏语北路康方言元音变迁——以德格话元音变迁为例

文章分析了德格话元音变迁的内因和外因,揭示了语音内外因素制约元音演化的轨迹。指出德格话元音演化过程中,虽然偶有外因渗透影响元音演化,但终究没成为演化通则。德格话元音演变的主要方式是条件音变,条件包括声母和辅音韵尾,其中辅音韵尾成为使元音发生演变的主要诱因。     

"中国英语"语言特征及其社会历史成因探究

当今英语已经成为了国际语言,它不再为一国或一个民族专有,而是一个中性信息媒介。“中国英语”作为“世界英语”的组成部分在争议中诞生。“中国英语”是以一般英语规范为核心的中国人使用的一个英语变体,其特征深受中文和中文思维方式的影响,并在语音、词汇、句法和语篇上都有体现。共时角度下“中国英语”的语言特征,包含了其产生的文化心理原因;“中国英语”产生所经历的三个时期——从洋泾滨英语到通用语最后到“中国英语”——都有其社会历史成因。这就证明了“中国英语”不仅是客观存在的,而且还具有深刻的时代性。     

兰鼎生物:抢占生物科研制高点

2004年召开的苏州工业园区科技发展资金兑现会上,苏州兰鼎生物制药有限公司成为引人注目的明星,这家公司的国家一类新生物制品重组人尿激酶原等4个项目,一下子捧回了270万元科技发展资金,成为当年获园区科技发展资金最多的科技企业.     

Study on anti-pollution nano-preparation or dimethomorph and its performance

The photocatalysis of nanometer TiO2/Ag was modified by sodium dodecyl sulfate, and its behavior of adsorption for pesticide was investigated on the surface of catalyst. Four kinds of water-solubility preparations were prepared by using TiO2/Ag, modified TiO2/Ag by 0.5% SDS, TiO2 and nothingness as photocatalyst with dimethomorph as effective component. They were besmeared on a piece of glass, and the photocatalytic experiment was done in sunlight. Degradation rates of 1.2 % dimethomorph are 71.5 %, 68.0 %, 45.5% and 28.3%, respectively, when it was degraded in five days. Degradation rate of 10% dimethomorph is 97.3% in eight days in sunlight and ti/2 is 2.8 d in nano-preparation, when it was sprayed on small cabbages after being diluted in rudimental experiments of toxicity for crop. The nano-preparation is of better biologic activity, the virulence of which is 1.235 times as great as original pesticide and 1.245 times as ordinary preparation under the same condition.     

俄语讲演体语言特点试析

俄语讲演体是介于日常口语与书面语之间的一种语言变体。俄语讲演体的研究应与演讲文化的发展相适应，并将话语结构形散神聚、句法结构趋于简化、语句分解、词语重复、词序倒装、引入口语性对话成分及名言警句等视为这一变体的基本特点。     

电流变体单链的轴向应变对导电性质的影响

研究了由平均直径为２１０μｍ的玻璃球在硅油中加直流电场后形成的单链的导电行为，主要研究了链的轴向应变对其导电性质的影响。     

"双言现象"初探

全文分三部分 :第一部分是对双言现象的总体介绍 ,包括双言现象的定义、人们对其两种变体的不同态度 ;第二部分着重分析了双言现象的变化 ;第三部分重点分析中国在五四运动以前存在的双言现象及其随后消失的主要原因。