亚麻油改性酚醛树脂制备及其耐热性能

利用亚麻油改性酚醛树脂（PF），得到高性能的摩阻材料用树脂基体．综合热分析结果显示改性PF在320～600℃间失重53．11％，普通PF失重73．51％；普通PF热分解峰为400～425℃和540～600℃，而亚麻油改性PF热分解峰为440～470℃和600～660℃，表明亚麻油改性PF的耐热性和热稳定性能均得到很大提高．推导了亚麻油的改性机理和改性PF的结构特征；发现亚麻油参与反应并成为聚合物结构的一部分，亚麻油改性PF固化后的结构特征是互穿聚合物网络（IPN）．     

桐油改性酚醛树脂摩阻材料的研究

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。     

无石棉摩阻材料的研究——Ⅰ.玻璃纤维增强摩阻材料

本文选用热分解温度为461℃,700℃时残留物为63%的硼改性酚醛(P树脂)与丁腈橡胶共混后作为基体,以玻璃纤维作增强剂。对该体系制成的摩阻材料进行了配方、制备工艺及复合机理等较系统的研究。结果表明,在33%基体含量中,丁腈橡胶占4～7%时具有良好的增韧性及其它综合性能。含21%玻璃纤维的无石棉摩阻材料离合器片,其性能已符合国家标准,可以进行扩大生产。     

硼砂改性竹纤维增强摩阻材料摩擦学研究

对竹纤维采用硼砂耐热改性处理,采用热压法制备改性竹纤维增强树脂基复合材料试样,并进行改性竹纤维表面结构分析、热失重分析、复合材料摩擦学性能测试和磨损表面形貌观察.研究结果表明,竹纤维经硼砂耐热改性后,其增强摩阻材料的摩擦学性能有一定提高,尤其是高温时抗热衰退性和耐磨性得到显著改善.试验中硼砂溶液质量分数为12%,处理时间为30 min的试样综合摩擦磨损性能最优.硼砂改性可提高竹纤维阻燃性,使复合材料在高温磨损后的表面仍有大部分竹纤维存在,保持对树脂基体的增强效果,提高了材料的摩擦学性能.     

高性能酚醛复合材料工艺研究及应用

用桐油和纳米SiO_2对酚醛树脂进行改性,合成品质优良的树脂,根据桐油加入工艺条件,探讨其合成改性机理。采用热分析系统,对桐油/酚醛和纳米SiO_2/桐油/酚醛两种改性树脂进行了测试,通过对TG/DTA曲线研究,展示了它们的热解动态。结果表明它们的耐热性均显著优于普通的酚醛树脂,样品初始热分解温度在420℃以上。桐油改性的酚醛树脂,具有优良的醇溶性,柔韧性,使合成更易于控制,对产业化具有重要意义。制成摩擦制动材料,测试了其摩擦性能。     

钼酚醛树脂的合成与性能研究

对钼改性酚醛树脂的合成进行了研究，讨论了各因素对合成工艺的影响，确定了最佳工艺参数。制备的钼酚醛树脂热分解温度为522℃，600℃下失重率仅为17．5％，其它性能达到普通酚醛树脂的标准。     

高性能摩阻材料用酚醛树脂

通过冲击强度、红外光谱、热分析、刹车片试验等手段研究了稀土和亚麻油对酚醛树脂的改性作用,结果表明,稀土离子将酚羟基封锁减少了酚羟基对其邻位上亚甲基的影响,提高了树脂的耐热性,亚麻渍的烷基链起到内增韧的作用,改善了树脂的脆性。通过稀土和亚麻渍的双改性,合成出高性能摩阻材料用酚醛树脂。     

汽车摩擦材料树脂基体的选择

通过对５种不同树脂基体的热性能和以其为基体的摩擦材料的力学性能及摩擦磨损性能研究，得出如下结论：在所研究的树脂中，其热分解温度都较高．其中进口环氧改性树脂、国内吉林产酚醛树脂和浙江产腰果壳油改性酚醛树脂的热分解温度都超过５２０℃，且前二者在５００℃时热分解余重都超过７０％，说明这两类树脂热分解温度高，分解缓慢，是一种较理想的树脂基体材料．从冲击强度、三点弯曲性能、硬度等力学性能指标考虑，以上３种树脂基体也较优．从摩擦磨损性能看，进口漆树粉改性树脂及吉林产树脂有较高且稳定的摩擦因数、热衰退较小．综合各种性能指标，树脂粘结剂以国产酚醛树脂、进口环氧改性树脂和漆树粉改性树脂为佳．     

纳米蒙脱石和坡缕石复合PF基摩擦材料性能

在苯酚预聚物中分别添加其质量分数为1.5%的纳米蒙脱石(M)和坡缕石(P),原位聚合了2种酚醛树脂(分别记为PF/M和PF/P).用热分析仪对其进行了TG分析.将合成的PF/M和PF/P为基体分别制备半金属摩擦材料,按照GB5763—2008在XDMSM定速式摩擦磨损试验机上进行摩擦学性能测试.结果表明:纳米粒子份数为1.5%PF/M的耐热性及其摩擦材料的摩擦学性能均明显优于未有纳米粒子复合的PF和PF/P,在600℃时PF/M残炭率较PF/P高4%,较PF高12%,所制备的摩擦材料试样的抗热衰退温度较PF/P和PF树脂摩擦材料分别提高约50℃和100℃,且摩擦因数稳定,350℃高温时段的磨损率较FP-1.5和F-0.0分别降低16.8%和27%.     

硼硅改性对酣醛泡沬耐高温性能的影响

使用硼酸和硅溶胶,通过控制体系的pH,合成了可发泡的硼硅改性酚醛树脂,并制备出硼硅改性酚醛泡沫。经测试表明,该材料具有良好的耐高温性能,其长期使用温度可达 230 ℃,热分解温度为500 ℃ ,800 ℃时热失重率仅为55%。同时研究了pH对硼硅改性酚醛树脂的可发性和稳定性的影响,结果表明,控制体系pH = 6.5~7.5为宜。     

Markedness and its Interpretation in Language Use

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.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

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.     

Features of Women's language

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.     

A computer generator for randomly layered structures

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

低渗透非均质砂岩油藏启动压力梯度研究

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。     

On Tragic Consciousness In The Works By Ernest Hemingway

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.     

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

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。     

An Index mechanism for multi-scale view in spatial databases

There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.     

Jane Eyre——A Feminist In The 19th Century

In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.     

《Chinese Science Bulletin》SUBJECT INDEX TO VOLUME 59(2014)

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