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1.
波导法测量有衬底介质复介电常数和复磁导率   总被引:1,自引:0,他引:1  
提出了应用微波网络分析仪测量有衬底介质的复介电常数和复磁导率的原理、方法,并给出了计算实例。该方法适用于吸波材料研究中多层介质样品的电磁参数的测量,具有样品易于制作、测量简单准确等优点,并可在较高的频率下使用。  相似文献   

2.
极薄介质复介电常数的测量   总被引:2,自引:0,他引:2  
极薄介质复介电常数的测量赵克玉,许福永(兰州大学电子与信息科学系,兰州730000)对于薄片、薄膜等介质材料,用常规的方法测量复介电常数会遇到困难。本文设计了如图1所示的测试终端,用长为l的介质材料作基质,完全填充于尺寸为a×b的矩形波导中,将厚度为...  相似文献   

3.
带线法同时测量复介电常数和复磁导率   总被引:1,自引:0,他引:1  
提出了可以宽频带扫频同时测量电磁介质的复介电常数εr和复磁导率μr的带线法,推导出了由带线的S11及S21表示εr及μr的理论公式。对带线夹具进行了设计,给出了铁氧体及吸波材料样品的测试数据。测试表明,带线法具有准确性高、特别适宜大损耗材料的测量和容易操作等优点。  相似文献   

4.
提出了可以宽频带扫频同时测量电磁介质的复介电常数εr和复磁导率μr的带线法,推导出了由带线网络的S11及S21表示εr及μr的理论公式.对带线夹具进行了设计,给出了铁氧体及吸波材料样品的测试数据.测试表明,带线法具有准确性高、特别适宜大损耗材料的测量和容易操作等优点.  相似文献   

5.
从光学原理出发,分析了空间波法测介质板介电常数时的表面反射问题,指出它对测量结果的影响与介质材料的特点及不同的测量方法有关,并结合几种低耗介质材料的测量结果,对上述分析进行了实验验证,最后还对影响测量的准确度与重复性的几个具体问题进行了讨论。  相似文献   

6.
带线法的测试范围和误差分析   总被引:2,自引:0,他引:2  
介绍了在微波频率下用带线法测量复介电常数和复磁导率的测试原理。对测试范围和测试误差进行了讨论。适当地选择样品长度,复介电常数εr和复磁导率μr的测量误差可在±5%以内。测试范围与测试参数值的配合有关,该方法适合微波吸收材料和一般非低损耗材料的测量。  相似文献   

7.
采用终端短路同轴开口波导技术,将开口同轴波导作为传感器,测量样品加载时的复反射系数,运用优化迭代反演求得待测材料的相对介电常数.详细介绍了所采用的理论模型和测量系统,测量了一些常见介质材料的复反射系数,复反射系数参考值与理论计算值基本吻合,证明了该方法的合理性及可行性.  相似文献   

8.
提出了一种测量微波集成电路基片复介电常数的新方法。通过测量贴于开口矩形波导外的介质基片的等效导纳值,可计算得到基片的介电常数和损耗角。经过理论分析,给出了修正的导纳计算公式和求解复介电常数的优化算法。  相似文献   

9.
将椭圆偏振测量法(椭偏法)的电磁频谱从原来可见光、红外波段拓展到毫米波段,对毫米波椭偏法测量原理进行理论分析,使用已构建的实验装置进行测量.通过对测量结果的分析,选择合适的入射角,经过大量测试,计算出被测介质材料的复介电常数.  相似文献   

10.
介绍了在微波频率下用带线法测复介电常数和复磁导率的测试原理.对测试范围和测试误差进行了讨论.适当地选择样品长度,复介电常数εr和复磁导率μr的测量误差可在±5%以内.测试范围与测试参数值的配合有关.该方法适合微波吸收材料和一般非低损耗材料的测量  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.
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   

15.
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   

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.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

19.
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   

20.
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   

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