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1.
多碎石沥青混合料SAC路用性能   总被引:3,自引:0,他引:3  
对SAC的2种级配(SAC-25,SAC-20)、3种沥青结合料(A-70,A-30,SBS改性沥青)的高温性能和单轴贯入剪切试验、低温性能、水稳性能等进行了比较试验研究.研究结果表明,采用骨架密实型级配和硬质沥青,其混合料的动稳定度DS约为石油沥青(A-70)混合料的2倍,单轴贯入剪切试验抗剪强度约为石油沥青(A-70)混合料的1.3倍,为SBS改性沥青混合料的1.1.倍,适用于南方湿热地区沥青路面中下面层.  相似文献   

2.
沥青混合料级配优化设计   总被引:12,自引:0,他引:12  
为了优化沥青混合料(HMA)集料级配,提高路面抗车辙性能,延长路面使用寿命,应用粗集料单因素骨架密实性检验和贝雷法相结合的研究方法,研究了集料质量分数、粗集料比例(CA)值、关键筛孔通过率对级配骨架的影响。结果表明:兰州辉长岩AC-16粗集料骨架结构的最优配比为5.4(19~16mm):30.6(16.0~13.2mm):24(13.2~9.5mm):40(9.50~4.75mm),优化的骨架集料级配的CA值为0.67。对该级配和常规密级配沥青混合料的高温性能、低温性能、水稳定性等路用性能进行了对比研究,证实了优化级配具有更优良的路用性能。  相似文献   

3.
设M为紧致、可定向、不可约、不可约、不含本质平环及本质环面的3-流形,并且M只有一个环面分文T0,证明了:如果r1,r2为T0上使M(r1)可约,且使M(r2)含有一个本质环面的两个斜度,则(r1,r2)≤3.  相似文献   

4.
通过自行配制高固含量(70.64%)的乳化沥青制备水泥乳化沥青胶浆,研究其油灰比在0.30到1.06之间变化时,对应的抗压、抗折强度变化规律。结果表明:随着油灰比的增大,抗压强度、抗折强度都不断减小。  相似文献   

5.
改性沥青结合料低温性能评价指标   总被引:12,自引:0,他引:12  
针对高寒多年冻土区特点,选用基质沥青与丁苯橡胶(SBR)改性沥青,通过测力延度试验进行沥青结合料低温性能多指标评价对比,据此提出韧性比指标与常规技术指标试验、夏普计划(SHRP)动态剪切试验及弯曲粱流变仪试验等不同试验指标进行相关性分析。结果表明:韧性比指标与动态剪切试验、弯曲流变仪试验及常规技术指标有良好的相关性,采用韧性比作为评价沥青结合料低温性能的主要指标合理可行:为保证低温性能,建议多年冻土地区沥青韧性比不宜低于4.5。  相似文献   

6.
在微扰QCD因子化方法的框架下计算了B→Ds^(*)ρ^0,B+→Dx^(*)+ρω^0和B^0→Ds^(*)ρ-衰变道的分支比.通过计算发现衰变道B→Ds^(*)+ρ^0,B^+→Ds^(*)+ω^0和B^0→Ds^+ρ^-的分支比在10^-5量级,而B^0→Ds^(*)+ρ^-衰变道的分支比最大,约为1.2×10^-4.在这些衰变道中,对于末态包含两个矢量介子的衰变,径向激化的贡献是主要的,并且大于80%;而两个横向激化的贡献是被rDs^(*),rρ(ω)的幂次压低的.  相似文献   

7.
以十二烷基硫酸钠(SDS)和辛基酚聚氧乙烯醚(TX—100)为模板剂,正硅酸乙酯(TEOS)为硅源,乙二胺为碱性介质,当n(TEOS):n(Fe(NO3)3):n(SDS):n(H2NCH2CH2NH2):n(H2O)=1:0.008:0.10:0.05:2.2:120合成Fe—Si介孔分子筛,通过XRD、IR、N2吸附脱附、NH3-TPD等方法对分子筛的晶体结构和表面物性进行了研究,结果表明,合成的分子筛具有典型的六方介孔结构特征,孔径分布较窄,具有较大的比表面积和较强的酸性。  相似文献   

8.
采用以Ce(NO3)3,Sm(NO3)3和(NH4)2CO3为反应物,聚乙二醇(PEG)为分散剂的改性共沉淀法合成了Ce0.8Sm0.2O1.9纳米晶.在PEG存在条件下,从Ce(NO3)3,Sm(NO3)3和(NH4)2CO3的混合溶液中生成了Ce2(CO3)3和Sm2(CO3)3的共沉淀纳米线.实验结果显示,采用该方法得到的共沉淀团聚很少,且随着聚乙二醇添加量的增加,纳米线的线径减小.将纳米线在很低的温度(约300℃)下焙烧基本形成了Ce0.8Sm0.2O1.9纳米晶,比通常的共沉淀法的焙烧温度(约500℃)降低了约200℃.  相似文献   

9.
本文主要采用色谱/质谱联用(GC/MS)及热失重(TG)等方法对比检测分析加煤和未加煤沥青瓷漆炼制过程所挥发气体的成分和挥发量.从实验结果可知,加煤沥青瓷漆比未加煤沥青瓷漆的挥发性气体量明显减少,也未曾检出具有较大毒性的致癌物质.  相似文献   

10.
添加炭黑对石油沥青基球形活性炭孔结构的影响   总被引:2,自引:0,他引:2  
以添加炭黑的石油沥青为原料,采用悬浮成球的方法和CO2活化工艺,制得了比表面积约为1493m^2/g而且富含3.6nm左右中孔的石油沥青基球形活性炭(PSAC)。通过吸附性能测定和XRD分析,对添加炭黑和未添加炭黑的PSAC的孔结构进行了对比研究,少量炭黑的加入导致了很大程度炭微晶层面的破坏和微晶细化,同时沥青与炭黑在收缩应力的作用下发生界面剥离,为CO2进入球体内部提供通道,促进了孔隙的发展。  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.
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   

18.
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   

19.
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.  相似文献   

20.
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   

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