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1.
在线式磁光隔离器的设计与分析   总被引:1,自引:0,他引:1  
提出了一种新的与偏振无关的在线式磁光隔离器结构,给出了设计思想和工作原理.利用矩阵光学理论对磁光隔离器的正向插入损耗和反向隔离进行了分析.实验和理论分析表明该器件的性能良好.  相似文献   

2.
BIG磁光隔离器的研制   总被引:1,自引:0,他引:1  
用非稀土磁光石榴石晶体,金女铁硼永久磁铁和格兰一汤姆逊棱镜研制的磁光隔离器.实验结果在1.52μm波段正向插入损耗<0.6dB,反向隔离度>36dB.  相似文献   

3.
本文报导了用磁场调制反射光谱对磁光晶体进行的光学测量。实验结果表明,磁场调制反射光谱可有效地用于磁光晶体电子态结构的研究,从而提出了一种研究磁光材料光学特性的新的测试手段。  相似文献   

4.
在线式磁光隔离器的设计与分析   总被引:6,自引:0,他引:6  
提出了一种新的与偏振无关的在线式磁光隔离器结构,给出了设计思想和工作原理,利用矩阵光学理论对磁光隔离器的正向插入损耗和反间隔离进行了分析,实验和理论分的表明该器件的性能良好。  相似文献   

5.
研究了泵浦光的不同通光方向和偏振方向对Nd^3+:KGd(WO4)2晶体和Yb^3+:KGd(WO4)2晶体荧光光谱的影响.实验表明在不同情况下对晶体荧光强度影响较大,因此在设计用激光二极管泵浦的激光器时,应考虑合适的泵浦光偏振方向和入射在晶体上的轴向,其中泵光的通光方向比泵浦光偏振方向对晶体的荧光强度的影响更大.对按晶轴切割的这两种晶体,相同实验条件下,荧光强度Ic〉Ib〉Ia;对于按折射率主轴切割的荧光强度INp〉INg〉/INm;在通光方向为c轴,偏振方向平行b轴时得到了最大的荧光强度.  相似文献   

6.
光开关是全光网络中的关键器件,主要用来实现光层的路由选择、波长选择和光交叉连接等功能。研制一种利用法拉第效应、光纤型偏振分/合束器、磁光晶体光纤高速磁场控制技术的全光纤磁光开关。这种微型的磁光开关具有开关速度快、结构简单、柔韧可弯曲和易于集成等特点。  相似文献   

7.
采用射频磁控溅射方法制备了DyFeCo非晶磁光薄膜,研究了氩气压、溅射功率对DyFeCo薄膜性能的影响.实验表明:反射率随氩气压升高而降低,矫顽力随氩气压升高而逐渐增大,达到一定值时克尔回线反向,随后矫顽力又逐渐减小,高气压下的矫顽力温度特性较低气压下的矫顽力温度特性要好,但氩气压进一步升高,磁光克尔回线矩形度变差.本征磁光克尔角随氩气压升高而增大,到达最大值后又逐渐减小.反射率随溅射功率增加而升高,到达最大值后又逐渐下降.矫顽力随溅射功率增加而逐渐增大,到达最大值后,磁光克尔回线反向,然后矫顽力又逐渐减小  相似文献   

8.
超磁致伸缩微位移执行器控制系统研究   总被引:1,自引:0,他引:1  
以单片机和上位PC微机为控制核心,设计并构建了利用超磁致伸缩棒开发的超磁致伸缩执行器的计算机闭环控制系统,完成了相应的软硬件设计.结合所开发的超磁致伸缩微位移执行器的结构建立了传递函数模型,针对微位移执行器控制系统进行了数字PID控制器设计,通过实验得出,在不降低其相对稳定性情况下数字控制系统的精度提高,为进一步提高超磁致伸缩执行器的精度、改善整个系统的动态特性奠定了基础.  相似文献   

9.
为深入了解液晶的磁旋光特性,利用矩阵方法分析研究了液晶的旋光效应,导出了液晶旋光的矩阵表示.通过测量磁场作用下向列型液晶的旋光角及透射比,研究了液晶的磁旋光特性.详细分析了磁场对液晶分子轴旋转和透射比的影响,做出了液晶分子轴旋转角和透射比与磁场强度关系的曲线.通过改变磁场方向进行实验测试.发现液晶的旋光方向与垂直入射液晶盒的磁场方向无关。  相似文献   

10.
分析了 4 X 密度磁光盘模压信息的特性,根据国际标准所提出的测试条件自行研制了测试系统,阐述了头信号和槽信号的测试方法,给出测试实例.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

15.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

19.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

20.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

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