华东自然环境下CFRP片材的耐久性能

在华东地区自然暴露环境条件下,对土木工程加固常用的2种碳纤维增强复合材料(CFRP)片材共40个试件进行自然老化3 a的耐久性能试验.考察碳纤维片材的抗拉强度、弹性模量、伸长率等主要的力学性能指标随老化时间的变化.结果表明,随着老化时间的延长,两种片材的抗拉强度和伸长率均略有降低,并且其伸长率的变化趋势与抗拉强度的变化趋势类似;随着老化时间的延长,两种片材的弹性模量变化不大.     

平纹铺层及三维角联锁复合材料热氧老化后低速冲击及剩余弯曲性能

以平纹铺层和三维角联锁碳纤维/环氧树脂复合材料为研究对象,探究其在180℃高温下分别老化4、8、16和32 d后的低速冲击响应,并结合其冲击后弯曲性能,比较两种结构复合材料抗冲击性能随老化时间的变化规律。结果表明:随着老化时间的增加,冲击加载下平纹铺层和三维角联锁纤维环氧树脂两种复合材料试件的最大冲击载荷减小,能量吸收率增大,承载性能退化;相同老化条件下,三维角联锁结构试件的剩余模量和强度保留率均高于平纹铺层试件。两者微观形貌的分析表明:平纹铺层结构试件易在热氧老化过程中形成连续的层间裂纹,并在外加载荷作用下扩展造成层间失效;三维角联锁结构试件因厚度方向的接结纱作用,界面裂纹扩展受阻,从而缓解热氧老化引起的界面性能退化。     

超热老化对浇注式沥青混合料高温性能影响研究

浇注式沥青混合料拌合温度高达240℃,拌合时间超过45 min,该条件下浇注式沥青将发生严重的热氧老化,然而超热老化温度和老化时间对浇注式沥青混合料高温性能的影响规律报道较少。对此采用车辙试验对不同超热老化温度和老化时间的浇注式沥青混合料高温性能变化规律进行了研究。研究结果表明:动稳定度与超热老化温度高度相关,高温抗变形能力随超热老化温度升高而不断升高;动稳定度与超热老化时间具有较高的指数相关性,随着超热老化时间延长,动稳定度值呈先缓慢上升到快速上升趋势。在确保浇注式沥青混合料高温性能的同时,必须合理控制老化温度和老化时间,解决由于超热老化导致其抗疲劳开裂能力降低的问题。     

老化玄武岩纤维沥青混合料冻融劈裂试验研究

为了研究不同条件下玄武岩纤维沥青混合料的冻融劈裂性能,通过向沥青混合料中掺加玄武岩纤维制备试验试件,并测试分析不同条件处理试件的冻融劈裂性能。研究结果表明：玄武岩纤维可改善沥青混合料的冻融劈裂性能,同时还可增强紫外老化和冻融循环、热氧老化和冻融循环下沥青混合料的韧性。玄武岩纤维掺量为0.6%时,4次冻融和未老化下,沥青混合料的劈裂强度较未冻融未老化及未掺玄武岩纤维下分别减小0.52%、14.47%、21.45%、31.78%;4次冻融和紫外老化下,0.6%玄武岩纤维掺量沥青混合料的劈裂强度较未冻融老化及未掺玄武岩纤维下分别减小5.94%、19.64%、27.65%、39.28%;紫外老化和未冻融下,0.6%玄武岩纤维掺量沥青混合料的劈裂强度较未老化未冻融及未掺玄武岩纤维时增大3.88%。热氧老化未冻融下,0.6%玄武岩纤维掺量沥青混合料的劈裂强度较未老化未冻融及未掺玄武岩纤维时增大1.29%。紫外老化、热氧老化及未冻融下,0.6%玄武岩纤维掺量沥青混合料的劲度模量较未老化未冻融时分别增大1.01%和10.23%。     

PBO纤维片材预应力外粘结加固集成新技术

近年采用外部粘结纤维增强复合材料(FRP)来加固结构越来越受到许多研究开发机构和生产单位的重视。结合作者在FRP方面的研究成果和最新开发出的高强高性能的PBO纤维材料，系统地提出了一种更为有效的预应力外粘结加固方法；通过与玻璃纤维、炭素纤维和芳纶纤维等的比较，认清了新型PBO纤维材料的特性；根据既有的试验和研究成果提出了一套完整的预应力加固方法的流程，包括概念、原理和几种降低端部界面应力和新型锚固的措施；室内小型试验和室外大型试验的结果表明，PBO片材预应力技术能够提供令人满意的加固性能。     

不同热氧老化环境下SBS改性沥青及其混合料性能研究

【目的】探寻沥青及沥青混合料逐渐老化对沥青路面路用性能的影响。【方法】对不同热氧老化环境下SBS(I-D)聚合物改性沥青的常规指标、流变性能及以其制备的AC-13C沥青混合料的高温稳定性、低温抗裂性、水稳定性及单轴压缩动态模量开展试验研究。【结果】随着热氧老化程度的不断加深,沥青黏韧性及抗塑性变形的能力逐渐降低,脆性逐渐增强;随着热储存时间的增加,沥青软化点、5℃延度和针入度先升高后降低,135℃黏度逐渐升高;随着热氧老化程度的不断加深,沥青混合料高温抗车辙能力逐渐提高,低温抗开裂及抗水损害能力逐渐降低;沥青混合料动态模量随着温度的升高而降低,随着热氧老化程度的加深及加载频率的增大而升高,但温度为35、50℃时其变化趋势有所改变。【结论】随着热氧老化程度的不断加深,沥青混合料高温性能得到改善,低温及水稳定性能降低,该研究成果在实际工程应用中具有一定的价值。     

热氧老化对高韧性环氧沥青及其混合料性能的影响

通过热氧老化前后的拉伸试验和黏度试验评价高韧性环氧沥青的抗老化性能,通过马歇尔试验、劈裂试验、低温小梁弯曲试验及四点弯曲疲劳试验考察热氧老化对高韧性环氧沥青混合料性能的影响;并与美国环氧沥青和日本环氧沥青作对比。结果表明,热氧老化对三种环氧沥青及混合料的性能影响均不显著,老化后仍满足相关技术指标要求。其中,高韧性环氧沥青的拉伸强度、断裂伸长率和施工容留时间分别损失了8. 9%、11. 2%和4. 8%;其混合料的马歇尔稳定度、劈裂强度、低温破坏应变和疲劳寿命分别下降了6. 6%、5. 7%、8. 2%、8. 1%。高韧性环氧沥青的抗老化性能略逊于美国环氧沥青,而优于日本环氧沥青。     

热老化对核电主管道Z3CN20.09M不锈钢点蚀性能的影响

采用极化曲线和电化学交流阻抗法研究了400℃长期热老化对压水堆核电站一回路主管道用Z3CN20.09M铸造奥氏体不锈钢点蚀性能的影响.结果显示,材料的点蚀击破电位和电荷转移电阻随着热老化时间的延长而降低.热老化材料经550℃退火处理1 h后的点蚀击破电位和电荷转移电阻值均恢复到未老化材料的水平.研究表明此时α’相已经回溶,G相仍然存在,导致热老化试样点蚀性能下降的主要原因是α’相的析出.     

碳纤维／环氧树脂复合材料的热氧老化机理

以碳纤维/环氧树脂复合材料为研究对象，分别采用失重法、静态与动态（DMTA）力学性能测试和IR分析，研究了其热氧老化规律与机理。结果表明：在热氧老化条件下，碳纤维/环氧树脂复合材料的失重率与时间之间的关系服从指数规律；其弯曲强度保留率在25℃热氧老化条件下与老化时间无关，而在100和150℃条件下则随时间呈指数规律衰减，并且温度越高，其弯曲强度保留率下降越快；DMTA与IR分析结果一致，25和100℃的条件下，碳纤维/环氧树脂复合材料的老化形式为物理老化，而在150℃的条件下，则既有物理老化，又有化学老化。     

排水性沥青混合料热老化性能

为了研究排水性沥青混合料的热老化性能,首先研究了沥青混合料的热老化机理,然后通过对比分析确定了排水性沥青混合料的短期和长期热老化试验方法,最后对3种不同空隙率的排水性沥青混合料,分别研究了热老化对其高温稳定性、低温抗变形能力和抗水损害性能的影响规律。研究结果表明:热老化使结合料变脆,劲度模量变大,沥青混合料的动稳定度变大;相同热老化时间,随空隙率的增大,动稳定度增大,空隙率高的排水性沥青混合料低温抗弯拉破坏和抗收缩应力的能力越低;在同一空隙率下,排水性沥青混合料的最大弯拉强度和最大弯拉应变在老化后均减小;经过热老化处理后,排水性沥青混合料的抗水损害性能有所提高;在热老化时间相同条件下,空隙率越大,其抗水损害的能力就越差。     

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.     

Lower Paleozoic oil relationships within Williston Basin, Canada

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.     

An Analysis of Catherine＇s Character——Wuthering Heights

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.     

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.     

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.     

Design and analysis of generic LBS application developing platform

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.     

橡胶颗粒沥青混合料低温抗裂性试验研究

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.     

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.     

Quantitative trait loci （QTLs） for quality traits related to protein and starch in wheat

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.