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1.
通过调节水溶性聚合物配比和无机盐配比,可以使智能遮阳材料的转变温度、透光率、转变灵敏度及迟滞性等达到最佳.日间曝晒结果表明,透明状态的智能遮阳材料可使曝晒箱升温30℃,不透明状态的该材料可在同等条件下具有阻止曝晒箱内温度升高9℃左右的遮光效果,有利于缓解夏季的过热现象.该智能遮阳材料可耐1 000次高低温循环,5年以上的自然曝晒,凝固温度低于- 10℃,环境温度高于转变温度时可保持1年以上均匀稳定的白色不透明絮状.  相似文献   

2.
通过采用紫外光聚合诱导相分离法制备聚合物稳定液晶调光器件,利用紫外可见分光光度计来研究器件的不同厚度对聚合物稳定液晶调光器件电光性能的影响. 结果表明:随着器件厚度的增加,器件的关态透光率降低,阈值电压升高,饱和电压升高;当器件厚度为5 m时,聚合物稳定液晶智能调光器件的电光性能优良,未通电时,透光率高达97%,当施加40V电压时,透光率低于10%;响应时间非常短,灵敏度非常高,从关态到开态响应时间仅仅需要0.025 s,从开态到关态响应时间需要0.06 s. 这些优异性能使得基于聚合物稳定液晶的智能窗在室内光线智能管理领域有着巨大的应用潜力.  相似文献   

3.
在溶液温度为30~60℃时,研究了热电厂粉煤灰作为空气氧化硫化钠溶液的非均相催化剂,并对粉煤灰来源和用量、搅拌速度、反应温度、粒度和空气流速等因素对反应的影响进行了探讨。结果表明粉煤灰具有良好的催化活性,在溶液温度为30℃,粉煤灰用量为4%(质量分数,%)时,反应速率是无灰时的3.5倍,催化氧化反应的活化能为:10.868KJ/mol:空气流速从0.05--0.60L/s变化时,S^2 的氧化速率不受空气流速的影响。与新灰相比,五次重复旧灰的活性下降了约30%。  相似文献   

4.
制备了一种温致透光率可逆变化智能遮阳材料,研究不同原材料配比、温度、时间对透光率变化,以及水质和防腐剂对其抗霉变性的影响.结果证明:通过调节聚合物配比可使其透光率在80%~90%间变化;温度是智能遮阳材料透光率改变的主要因素;引入防霉剂和调整pH值可以使智能遮阳材料3~5年内不发生霉变.  相似文献   

5.
聚酰亚胺/凹凸棒土纳米复合物制备与表征   总被引:5,自引:0,他引:5  
通过溶液聚合法,以聚酰胺酸(聚酰亚胺前聚体)和凹凸棒土合成制备酰亚胺/凹凸棒土纳米复合物.其结构和性质通过动态力学分析仪(DMA),热失重分析仪(TG),透射电镜(TEM)测定,结果表明,在凹凸棒土含量为3%时,在聚酰亚胺基体中,其分散性较好,而在含量为7%时,凹凸棒土出现部分团聚现象.在使用温度超过330℃时,加入凹凸棒土的纳米复合物的储能模量(E′)下降较慢,玻璃化转变温度Tg和热分解温度均增加15~30℃.  相似文献   

6.
为了优化红曲多糖的过氧化氢法脱色工艺,在单因素实验的基础上,选择过氧化氢加入量、脱色时间和脱色温度为自变量、多糖脱色率为响应值,应用DesignExpert软件,采用响应曲面法,研究了各自变量及其交互作用对多糖脱色率的影响.利用响应面分析方法拟合得到了二次多项式回归方程的预测模型,并确定了红曲多糖过氧化氢法脱色的最佳条件:4mL多糖(8mg/mL)溶液中3%过氧化氢溶液的加入量为3.9mL,脱色时间为127min,脱色温度为65.6℃.该条件下红曲多糖脱色率为86.24%.  相似文献   

7.
污泥焚烧中重金属和碱金属气固转变区域   总被引:3,自引:0,他引:3  
通过污泥焚烧试验研究了尾部烟道不同温度区域重金属和碱金属的分布,发现每种金属都有自己的气固转变区域.因此可以通过温度控制对这些金属进行分类,从而达到分离利用的目的.根据金属的气固转化温度,可将它们分成四类:1A类金属在温度高于600℃以上的区域开始从气态转变成固态。包括Zn,Cd,P;B类元索转变温度为400℃.有Pb和Cu;C类有Na和Mg,其转变温度为300℃以下;D类在300℃到400℃时转变,主要有As.  相似文献   

8.
分析了调频调光法的工作原理,并采用自行设计的电子线路实现了LVD感应无极光源的调频调光.测试了在这种调光方法下工作的光源的光电特性,分析了调频调光的稳定性和可靠性.作为对比,对调压调光法下灯的性能也进行了测试.实验表明,LVD感应无极光源采用调频调光法时,调光范围为100%到35.5%,在整个调光范围内色温和显色指数分别有3.8%和4.7%的改变.  相似文献   

9.
超声-非均相催化氧化法处理苯酚废水   总被引:1,自引:1,他引:0  
研究了超声/H2O2/CuO、超声/H2O2/Ni2O3及超声/H2O2/MnO2非均相体系对苯酚的去除效果。以初始浓度25mg/L的苯酚溶液为处理液.催化反应在带夹套的玻璃器中进行。在超声声强4.97W/cm^2、H2O2加入量300mg/L、催化剂的加入量均为1g/L、溶液温度30℃的处理条件下,3种体系中超声/H2O2/CuO组合对苯酚的去除效果最好。超声辐照240min时,单独超声、超声/H2O2、CuO/H2O2及超声/H2O2/CuO对苯酚的去除率分别为24.0%,53.3%,13.8%和89.5%,表明超声、H2O2与CuO具有协同作用。溶液温度从20℃上升到55℃时,3种组合下苯酚去除率均随温度升高有明显增大,表明温度较高时C6H5OH去除过程中催化作用起主要作用而非超声空化作用。  相似文献   

10.
人造沸石负载TiO2光催化降解水中苯酚的研究   总被引:3,自引:0,他引:3  
采用溶胶-凝胶法制备人造沸石负载型TiO2光催化剂,用XRD分析了其晶型结构,以300W中压汞灯为实验光源对苯酚进行了光降解研究。考察了催化剂热处理温度、TiO2负载量、催化剂用量、降解温度、光强度和H2O2用量等因素对降解率的影响。结果表明,浓度为15mg/L的苯酚溶液,催化剂焙烧温度为5000℃,TiO2负载量为15.7%,用量为2~3g/L,在300℃连续光照3h时,苯酚溶液的降解率可达到87.4%。  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.
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   

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 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   

15.
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   

16.
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   

17.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

18.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

19.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

20.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

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