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1.
将纳米SiO2加入到环氧丙烯酸酯体系中,配制成紫外光固化涂料;对涂料涂膜的抗冲击强度、附着力、柔韧性、硬度、耐老化性能进行了测试,并对涂膜进行了热重分析.研究表明,涂料性能随着纳米SiO2用量的增加而提高,但当纳米SiO2的用量占总物质质量分数的5%时,再增加纳米SiO2的用量,涂料的某些性能反而下降;纳米SiO2较佳的加量为涂料质量分数的3%~5%,在此范围内,所制得的环氧丙烯酸酯紫外光固化涂料涂膜的硬度达3H,抗冲击强度达4.9N·m、附着力达1级、柔韧性达1mm.光泽度85%~90%、鲜映性8~9级、耐人工老化800h失光率18.7%~23.4%.  相似文献   

2.
为了制备耐热、阻燃性能优异的新型含Si环氧丙烯酸酯(EA)纳米涂层,以KH-570改性纳米SiO2和有机硅改性EA作紫外光(UV)固化组分,并在配方中加入纳米Mg(OH)2,制备了系列UV固化新型含Si EA纳米涂层。通过红外光谱仪、紫外可见光谱仪、热重分析仪等研究紫外光固化体系涂膜耐热、阻燃及光学性能。结果表明:在有机硅改性EA中添加KH-570改性纳米SiO2,可以提高纳米涂层热稳定性、阻燃性,同时使其保持优良透明性;当改性纳米SiO2含量达5%时,涂膜耐热、阻燃性能均最佳;同时在体系中加入Mg(OH)2,可进一步改善体系的阻燃效果。  相似文献   

3.
以改性纳米SiO2、γ-甲基丙烯酰氧基丙基三甲氧基硅烷(KH.570)、磷酸酯三丙烯酸酯(TEAP)及TDI-TMP加成物作紫外(uv)配方体系的功能成分,制备了含P、N及Si三重固化丙烯酸酯涂层。通过红外、紫外-可见、热重及阻燃性能测试仪等研究了不同阻燃体系下不同固化方式对环氧丙烯酸酯(EA)涂层阻燃及热稳定性能的影响。结果表明:EA体系双键转化率随纳米SiO2含量及固化重数的增加而提高;可见光透过率随KH-570、TDI-TMP的加入而改善;涂层阻燃及热稳定性随阻燃成分与其含量,及固化重数的增加而提高。  相似文献   

4.
采用共混法制备了基于环氧丙烯酸酯(EA)的含纳米SiO2粒子的无机-有机紫外光固化复合涂层,并对其结构、热稳定性和物理性能进行了检测.结果表明,纳米SiO2粒子在涂层内部形成了含Si—O—Si的交联网络结构,这种结构有助于改善涂层的热稳定性.SiO2的质量分数为5%时,复合涂层的热稳定性最高.随着SiO2添加量的增加,复合涂层的光泽度降低.加入适量的纳米SiO2粒子可以提高涂层的硬度,当添加量为3%~5%时,复合涂层的铅笔硬度可以达到3H.  相似文献   

5.
采用紫外光固化技术,通过机械共混的方法制备了甲基-多面体齐聚倍半硅氧烷(甲基-POSS)质量分数分别为1%,5%,10%,15%的环氧丙烯酸酯(EA)/POSS纳米复合材料.通过X射线衍射、扫描电子显微镜、EDS能谱分析及热重分析对环氧丙烯酸酯(EA)/POSS纳米复合材料进行研究.结果表明,在甲基-POSS质量分数较高时,EA/POSS纳米复合材料中存在甲基-POSS晶体,说明杂化材料中存在相分离.甲基-POSS在聚合物中以分子或团聚体的形式存在,并且随着POSS质量分数的增加,团聚体尺寸及数量都逐渐增多.甲基-POSS单体提高了复合材料的热稳定性,并且POSS的加入并没有影响聚合物的热降解机理.  相似文献   

6.
研究比较了纳米TiO2、纳米SiO2及其质量比11的混合物对以自制的LB-1、TG-3树脂为主要成膜物所制得的紫外光固化粉末涂料性能的影响.结果表明,纳米粒子的添加可提高漆膜的硬度、附着力、抗冲击强度,显著地改善漆膜的耐候性能,但同时会使漆膜的光泽度和鲜映性有不同程度的降低;纳米TiO2及纳米TiO2与纳米SiO2质量比为11的混合物的添加量分别为3.0%~5.0%、2.0%~4.0%的质量分数时,可制得综合性能理想的紫外光固化粉末涂料.  相似文献   

7.
通过溶液的方法实现了环氧丙烯酸酯和蒙脱土的插层,并在紫外光作用下利用光固化反应制备了环氧丙烯酸酯/蒙脱土纳米复合材料.利用X-衍射对材料样品进行了插层表征,对有机蒙脱土的流变性进行了测试,对样品的力学性能(拉伸强度?冲击强度)进行了测试.结果表明:有机化的蒙脱土具有一定的触变性;插层后有机蒙脱土的片层被撑开剥离;少量的有机化蒙脱土的加入可较大提高材料的性能.  相似文献   

8.
采用正交试验法研究无机纳米粉体的修饰工艺,主要包括:分散温度、分散时间和分散助剂的选择及用量,研究了改性纳米粉体用量对丙烯酸酯粘合剂稳定性、皮膜耐水性等性能的影响。研究结果表明:无水乙醇2%(对单体),40Be°硅酸钠溶液5ml,室温分散30min,确定为SiO2粉体表面修饰的工艺。纳米SiO2相对于纳米TiO2对粘合剂性能提升更加明显,也更易分散,且纳米SiO2用量为丙烯酸酯单体的0.6~0.8%时,可得到应用性能较好的纳米原位复合有机硅改性丙烯酸酯乳液。  相似文献   

9.
采用两种原位表面修饰的纳米SiO2(RNS和DNS)通过原位聚合的方法制备了纳米SiO2/MC尼龙6复合材料,测试了材料的力学性能,RNS和DNS的加入均能使MC尼龙6的力学性能有较大提高,在一定的范围内对复合材料同时具有增强和增韧的作用,RNS的影响要大于DNS;同时通过SEM、TGA等分析手段,考查了纳米SiO2在聚合物基体中的分散情况、热稳定性.结果表明,纳米SiO2粒子在基体中分布均匀,两种纳米SiO2的加入均大大提高了复合材料热稳定性,使MC尼龙6的起始降解温度分别提高10℃和21℃.  相似文献   

10.
邓艳丽  赵剑涛 《河南科学》2012,30(5):571-574
采用溶胶凝胶法制备SiO2纳米颗粒和机械共混法直接将气相法SiO2纳米颗粒分散在树脂中,然后通过紫外光固化制备纳米复合涂层.采用SEM观察SiO2在涂料的分散状态,并对涂层的光学性能和机械性能进行了测试表征.结果表明,采用溶胶凝胶法制备的SiO2在涂层中分散较好,制备的涂层透光性、雾度等光学性能较好;采用机械共混法分散气相SiO2制备的涂层SiO2团聚较多,透光性差,但由于气相法SiO2具有较大的比表面积,与树脂的结合性能较好,故其硬度、耐刮擦、耐冲击等力学性能较好.  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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