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1.
掺C60有机聚合物热折变特性的研究   总被引:1,自引:0,他引:1  
用阿贝折射仪测量了醇酸清漆本征膜、掺C60醇酸清漆膜、有机玻璃本征膜和掺C60有机玻璃膜折射率随温度变化的关系.实验表明C60可有效提高有机玻璃热折变的灵敏度,热光系数达-3.4×10-4/℃.本文还探讨了热诱导折射率变化产生的机理,它对研制新型数字热光开关材料具有一定的意义.  相似文献   

2.
用聚甲基丙烯酸甲酯作为载体,掺入C60形成复合有机聚合物材料,研究分析了该种材料折射率与温度变化的关系和有机聚合物中掺C60比例不同时,折射率随温度变化的不同的规律.结果表明:掺入C60的聚甲基丙烯酸甲酯聚合物折射率比纯净聚甲基丙烯酸甲酯折射率明显提高,掺C60复合物的折射率随温度升高而降低,而且C60含量越高,折射率对温度的变化越敏感.  相似文献   

3.
采用监测表面颜色和光泽压变化的方法,对红松木材醇酸树脂清漆、硝基清漆和聚氨脂清漆涂膜的耐光性进行了研究,结果发现,三种涂料受光后均易发生变色,但三种涂料的耐光性硝基漆最差,聚氨酯漆(PU)居中,醇酸树酯漆最好.建议在使用时添加紫外线吸收剂,提高漆膜的耐光性。  相似文献   

4.
采用燃烧法合成了SrAl2O4:Eu2+,Dy3+黄绿色长余辉发光材料,并对其进行醇酸清漆包覆.对包覆材料进行了水解后电导率、发光亮度及余辉衰减曲线的测定,利用红外光谱及热重分析对包覆层进行分析.结果表明合适量的清漆包覆对发光材料的发光性能影响很小,却能有效地改善其耐水性能.合适包覆量的质量百分比约为4.2-6.3%.  相似文献   

5.
1,3,2-二氧磷杂环己烷衍生物的合成   总被引:5,自引:1,他引:4  
采用5,5-二甲基-2-氯2-氧-1,3,2-二氧磷杂环己烷和取代苯胺及脂肪二元胺反应,合成了10个未见文献报导的目标化合物Ia~Ij.通过元素分析、IR、^1H NMR、和MS对其结构进行了表征.部分化合物的热重和差热分析表明.化合物最高失重速率的温区在220~400C,这与大部分高分子材料的热氧降解温区重叠.具有很好的阻燃配伍性能.在醇酸清漆和环氧树脂中的初步阻燃测试表现出很好的阻燃性能.  相似文献   

6.
用两步离子交换法制备的Tl -Na 离子交换玻璃波导,比Ag ,Li ,K 等离子制备的光波导更具优越性,避免了这些离子的不足之处,其折射率差可达0.26。在温度低于玻璃转变温度时,这些波导具有良好的热稳定性。Tl -Na 离子半径巨大差异而产生的应力,离子的极化以及克分子体积导致了折射率的变化。本实验用雅敏干涉仪来测量实验所得的折射率分布,本文详细描述了Tl -Na 进行离子交换来制作光波导的实验过程,并通过布格尔定律和激光特性得到光波导的折射率理论分布。最后,根据实验所得数据,以及对折射率分布有影响因素的研究,很好地解释了折射率分布的实验结果,提出的离子交换机理可很好地解释折射率分布。  相似文献   

7.
为了提高光纤表面等离子共振温度传感器检测的适用条件,减少传感器对待测传感参量折射率的限制,避免引入对温度敏感的低折射率媒介,本文中将具有大倏逝场的微纳光纤放置于蒸镀金属膜的氟化镁衬底上,得到光纤表面等离子共振温度传感器结构。结果表明:通过使用传输矩阵的理论模型计算该结构中光纤折射率和氟化镁折射率变化对透射率影响,结合光纤和氟化镁的热光系数,分别得到约118、35 pm/℃的温度灵敏度,在光纤折射率增大对透射谱产生蓝移和氟化镁折射率增大对透射谱产生红移的共同作用下,该传感结构综合得到约153 pm/℃的传感器灵敏度。通过计算明确金膜厚度、光纤直径和光纤-金膜接触区宽度等不同的结构参量对透射率的影响。  相似文献   

8.
研究了宽禁带Ⅲ-V族化合物半导体氮化铝(AIN)薄膜的折射率及其热光特性,采用棱镜──薄膜耦合装置和自动温控光波导测试仪,测出不同温度下氮化铝薄膜的波导特性,利用迭代法可得到AIN的折射率与温度变化的关系,并首次测得了AIN薄膜的热光特性。  相似文献   

9.
本文用光干涉法测定了几种透明固体高聚物薄膜的折射率,其精度为10~(-4),并在-60~120℃范围内,测量了光在样品中传播的光程随温度变化的曲线。从该曲线上得出了高聚物样品的玻璃转变温度、热膨胀系数和折射率温度系数等有用资料。结果表明,光干涉法是测定高聚物的光学、热学性质和研究其相态转变的简单、灵敏的实验方法之一。  相似文献   

10.
设计了一种新型的散射元——月牙形散射元。采用平面波展开方法,通过调节两个圆的半径、圆心距及背景折射率几个参数,优化了光子晶体线性缺陷波导结构,实现了高群折射率和低色散的慢光效应。模拟结果表明,通过调整两个圆的半径及圆心距,慢光的带宽和群折射率变化地规律明显,较容易寻找到高群折射率、低色散慢光。通过控制材料硅的折射率,可以实现慢光模式的选频。基于材料硅的热光效应,该结构有希望应用于光传感器等方面。  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.
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   

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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