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纳米Al2O3改性酚醛树脂在汽车制动摩擦材料上的应用 总被引:1,自引:0,他引:1
用偶联剂KH570对纳米Al2O3进行表面处理,经透射电镜检测,发现纳米Al2O3能够均匀有效地分散在酚醛树脂中,并确定了纳米Al2O3质量为树脂质量的6%时分散性最好.运用共混的方法,对酚醛树脂进行纳米Al2O3改性处理,分析了纳米Al2O3的质量为树脂质量的2%,4%,6%,8%和10%时,改性酚醛树脂对汽车制动摩擦材料性能的影响.结果表明:经过表面处理的纳米Al2O3改性醛醛树脂,当纳米Al2O3质量为树脂质量的6%时,酚醛树脂的性能提升最明显,酚醛树脂的热分解温度提高了41℃,且降低失重率,纳米Al2O3改性酚醛树脂制备的摩擦材料的摩擦系数最稳定,具有较低的磨损率. 相似文献
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通过对比试验,研究偶联剂改性纳米Al2O3粒子对丁腈改性酚醛树脂摩擦磨损性能的影响。结果表明:铝锆偶联剂添加到纳米Al2O3粒子改性丁腈酚醛可显著提高酚醛树脂的耐热性、增加摩擦系数、降低磨损率。 相似文献
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通过对比试验,研究偶联剂改性纳米Al2O3粒子对丁腈改性酚醛树脂摩擦磨损性能的影响.结果表明:铝锆偶联剂添加到纳米Al2O3粒子改性丁腈酚醛可显著提高酚醛树脂的耐热性、增加摩擦系数、降低磨损率. 相似文献
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采用改进的工艺方法合成了桐油改性酚醛树脂,将其作为粘合剂制备了摩阻材料。试验表明:酚醛树脂经改性后,树脂及材料的性能均得到较大的改善;与其他改性方法的材料相比,摩擦系数较高而稳定。表面分析提示这种材料的热分解温度较高、热摩损较小,而低温下的粘着磨损和磨粒磨损略高。探讨了摩擦前后表面层组成和结构的变化。 相似文献
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利用专利中所述的方法制备纳米Al2O3含量为酚醛树脂5%的纳米改性酚醛树脂。通过SEM分析其显微结构;并用该纳米改性酚醛树脂材料进行摩擦磨损试验,分析其热衰退性能。结果表明:纳米粉在酚醛树脂中的分散情况较好。纳米改性酚醛树脂较纯酚醛树脂的热衰退和耐磨性有很大提高。 相似文献
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合成了一种具有优异韧性和热稳定性的覆铜板用环氧大豆油内增韧改性酚醛树脂.采用FTIR表征了改性酚醛树脂的分子结构,用SEM观察了改性酚醛树脂样品冲击断面的微观形貌,并对改性酚醛树脂制备的覆铜板的性能进行了研究,以获得最佳的合成工艺.文中还对改性酚醛树脂的增韧机理进行了探讨,发现其主要反应机理为:部分环氧大豆油在叔胺催化下与酚羟基进行醚化反应,同时环氧大豆油与多元胺发生扩链反应,最终生成与酚醛预聚体接枝的长链环氧大豆油环氧树脂.当环氧大豆油添加量为30%、固化剂含量达7%时,树脂的综合性能较佳.扩链后的环氧大豆油具有显著的增韧作用,它与酚醛树脂构成内增韧的交联网络,内增韧结构对改善覆铜板的耐焊性起着关键作用. 相似文献
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为了进一步提高酚醛树脂的阻燃性能,在酚醛树脂中填充纳米硼酸锌4ZnO·B2O3·H2O粒子对其进行改性.实验中采用苯酚、甲醛和自制改性纳米硼酸锌为原料通过原位合成法制备了纳米硼酸锌4ZnO·B2O3·H2O/酚醛树脂复合材料,通过红外光谱(FT-IR)、扫描电子显微镜(FESEM)、热重-差热分析(TG-DTA)和氧指数测定仪(LOI)对复合材料进行表征和测试.结果表明,添加纳米硼酸锌4ZnO·B2O3·H2O后,酚醛树脂的热稳定性有了明显提高,特别是当添加量为7%时,复合材料氧指数达到最大值46.3,酚醛树脂的阻燃性能显著提高. 相似文献
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纳米铜对酚醛树脂及摩擦材料性能的影响 总被引:1,自引:0,他引:1
采用原位同生法成功地制备了纳米铜改性酚醛树脂.利用X射线衍射分析和透射电子显微镜对所制备的树脂进行了表征,结果显示酚醛树脂中的纳米铜粒子分散良好,粒径为10~40nm.通过热重分析、冲击试验和摩擦试验,分别研究了纳米铜对酚醛树脂及摩擦材料性能的影响,结果表明:随纳米铜含量的增加,酚醛树脂的初始分解温度和半分解温度先升高后降低,在其质量分数为7%时分别达到最大值;随纳米铜含量的增加,摩擦材料的冲击强度先增大后下降,在其质量分数为5%时达到最大值;纳米铜可改善摩擦材料的摩擦磨损性能,尤其在高温下可使摩擦材料的热衰退明显减轻,磨损率显著下降. 相似文献
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《安徽理工大学学报(自然科学版)》2015,(3)
矿用材料的性能对于矿山安全具有重要作用,而酚醛泡沫材料是其中应用广泛的一种,但酚醛泡沫材料的脆性限制了其在矿山上的应用,为了获得具有韧性的新型酚醛泡沫材料,对酚醛泡沫材料进行了改性研究。在酚醛树脂脱水阶段加入一定量的聚乙二醇,得到增韧改性后的酚醛树脂。再通过加入发泡剂、固化剂、表面活性剂发泡得到增韧的酚醛泡沫,然后测试聚乙二醇对酚醛泡沫力学性能的影响,研究得出,当聚乙二醇用量为2%并且分子量为1 000时,酚醛泡沫增韧效果达到最佳。 相似文献
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QING Hai-ruo 《成都理工大学学报(自然科学版)》2004,31(6)
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
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YUJia-shun HEZhen-hua 《成都理工大学学报(自然科学版)》2004,31(6):694-698
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod… 相似文献
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海南岛地体及其毗邻陆缘晚中生代—新生代古地磁研究和构造演化 总被引:9,自引:1,他引:9
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。 相似文献
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Yan Yun’an 《华南师范大学学报(自然科学版)》2014,(6):136-137
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with 相似文献
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Yuriko Aoki 《华南师范大学学报(自然科学版)》2014,46(6):135-135
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to 相似文献
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The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time. 相似文献
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R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree). 相似文献
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The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included. 相似文献
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Advances in wireless technologies and positioning technologies and spread of wireless devices, an interest in LBS (Location Based Service) is arising. To provide location based service, tracking data should have been stored in moving object database management system (called MODBMS) with proper policies and managed efficiently. So the methods which acquire the location information at regular time intervals then, store and manage have been studied. In this paper, we suggest tracking data management techniques using topology that is corresponding to the moving path of moving object. In our techniques, we update the MODBMS when moving object arrived at a street intersection or a curved road which is represented as the node in topology and predict the location at past and future with attribute of topology and linear function. In this technique, location data that are corresponding to the node in topology are stored, thus reduce the number of update and amount of data. Also in case predicting the location,because topology are used as well as existing location information, accuracy for prediction is increased than applying linear function or spline function. 相似文献