中浓度纸浆流变特性的数值模拟

为了研究中浓度纸浆受到剪切力后的流动特征,找到中浓度纸浆在流变过程中的变化规律,对中浓度纸浆在剪切室内剪切流动进行了数值模拟.考虑气体和纤维对纸浆纤维悬浮液的流变特性的影响,将其定义为具有屈服应力和剪切稀化特性的赫巴流体,建立了数值模拟方法.分析了纸浆在不同剪切力作用下的屈服过程,以及屈服应力、表观黏度和剪切稀化指数等物性参数,不同剪切室外径等条件时的流变特性.结果表明:在剪切室内,随着转速的增加,纸浆黏度减小,屈服区域增大,随着剪切室外径增大,纸浆黏度增大,运动区域减小;同转速时,随着屈服应力增大,纸浆黏度增大;随着表观黏度增大,纸浆黏度增大,运动区域减小;随着剪切稀化指数增大,纸浆黏度减小,运动区域增大.     

总固体和温度对污泥流变特性的影响

对污水厂的污泥进行流变特性分析,考察不同总固体(total solid,TS)下污泥的极限黏度、屈服应力、触变性等流变特征指标的变化规律,并重点探讨TS和温度对污泥流变特性的影响。结果表明:当活性污泥TS为0.86%时,剪切速率从0~100 s-1的过程中,污泥具有假塑性流体的特征,但随剪切速率的不断增大(100~1 000 s-1时),表现出胀塑性流体的特征,其流变特性可用Herschel-Bulkley模型来描述。屈服应力与TS的呈幂律关系;极限黏度和触变环面积与TS呈指数关系;污泥黏度和触变环面积随温度升高而呈现降低趋势,且低剪切速率对黏度这种趋势的影响更加显著。     

铁矿球团用膨润土的流变特性

根据宾汉流体流变学,研究球团用膨润土的流变特性,分析膨润土流变特性与生球强度的关系,查明不同离子对膨润土流变特性的影响。研究结果表明:通过测量不同剪切速率下膨润土悬浮液的剪切应力,对剪切速率和剪切应力曲线拟合得到的膨润土塑性黏度、屈服强度和表观黏度能表征膨润土的流变特性。膨润土塑性黏度越大,生球落下强度越好;离子对膨润土流变特性影响很大,K~+特别是Na~+显著提高膨润土的塑性黏度,提升膨润土的流变特性;Cl~-能保证膨润土具有较好的流变特性。而Mg~(2+)和Ca~(2+)降低了膨润土的塑性黏度,CO_3~(2-)使膨润土的塑性黏度、屈服强度和表观黏度均减小,SO_4~(2-)和HCO_3~-则使膨润土的流变特性大幅度地下降。     

TS和温度对污泥流变特性的影响

对污水厂的污泥进行流变特性分析,考察不同TS下污泥的极限黏度、屈服应力、触变性等流变特征指标的变化规律,并重点探讨TS和温度对污泥流变特性的影响。结果表明：当活性污泥TS为0.86%时,剪切速率从0增加到100s-1的过程中,污泥具有假塑性流体的特征,但随剪切速率的不断增大(100s-1到1000s-1时）,表现出胀塑性流体的特征,其流变特性可用Herschel-Bulkley模型来描述。屈服应力与TS的呈幂律关系;极限黏度和触变环面积与TS呈指数关系;污泥黏度和触变环面积随温度升高而呈现降低趋势,且低剪切速率对黏度这种趋势的影响更加显著。     

特低渗透储层渗流特征和影响因素

为了研究特低渗透储层渗流特征及影响因素,以鄂尔多斯盆地白豹油田为例,对特低渗透岩心的单相和两相渗流特征进行分析.结果表明,特低渗岩心单相渗流具有拟启动压力梯度,渗透率越小,拟启动压力梯度越大;其渗流曲线不再为一条直线,而为下凹型曲线,呈现非达西渗流特征;其流变曲线不是直线,而为上凸型曲线,流体为非牛顿假塑性流体,在较小外力作用下不发生流动,只产生弹性变形,只有当外力大于某值时,流体才发生流动,且具有明显的屈服应力;动极限剪切应力与渗透率的关系表明,动极限剪切应力随渗透率减小而急剧增大;随着剪切速率的增大,视黏度逐渐降低,在剪切作用之后,流体浓度具有变小的特性;油水两相渗流曲线说明束缚水饱和度和残余油饱和度偏高,共渗区较窄,且随着含水饱和度增大,油相渗透率快速下降,水相渗透率缓慢增长.岩心的渗透率大小、润湿性、水锁等因素均对渗流特征有影响.     

稠油蒸汽泡沫共混体系的流变性能研究

为了进一步加强对稠油蒸汽泡沫驱油过程中流体力学性能的认识,在油藏压力7.60 MPa下,利用高温高压流变仪测得了不同条件下稠油蒸汽泡沫共混体系的流变曲线.实验结果表明:稠油蒸汽泡沫驱油体系均为假塑性流体,其流变方程能很好地关联幂律模型;随蒸汽相饱和度和泡沫剂浓度升高,体系表观黏度增大;随蒸汽干度和温度升高,体系表观黏度降低;在低剪切速率时,表观黏度和温度关系满足Arrhenius方程,随着剪切速率增大,表观黏度和温度关系逐渐偏离Arrhenius方程;黏流活化能的绝对值随剪切速率增大而降低,在低剪切速率时,表观黏度对于温度变化更敏感.     

用UE10/PVA混合体系制备的O/W型生漆乳液的流变性

以漆酚基乳化剂(UE10)和聚乙烯醇(PVA)为混合乳化剂制备了水包油(O/W)型生漆乳液(RLE).研究了UE10与PVA的质量比、混合乳化剂浓度(cME)、水与生漆(RL)的质量比、温度和贮存时间对RLE流变性的影响.结果表明,RLE的黏度随着PVA用量的增加而增大;在cME较低时,RLE都有剪切变稀的特性,表现出假塑性流体的行为,其流变曲线能与Casson和Herschel-Bulkley模型良好拟合;当cME≥10.0%,RLE则表现出膨胀型流体的特征,其流变曲线能与Herschel-Bulkley模型良好拟合,不能与Casson模型较好地拟合.RLE的黏度随着贮存时间的增长而增大,但假塑性流体特征未变;RLE的黏度随着温度的升高而降低.     

不同粒径尾砂料浆塌落度和屈服应力关系

尾砂料浆的流变特性既是水砂充填管道输送设计的重要指标,也可为尾砂胶结料浆的流动特性评价提供参考。基于标准塌落筒试验和流变试验,获得了不同质量浓度下4种尾砂料浆的塌落度和剪切屈服应力。结果表明：在料浆塌落度变化较大的质量浓度区间内,粗、细粒径尾砂料浆的塌落度均随料浆质量浓度的增加而减小,但细粒径尾砂料浆塌落度减小速度更快;随着质量浓度的增加,细粒径尾砂料浆的剪切屈服应力呈指数形式增大,而粗粒径尾砂料浆的屈服应力的变化相对不显著。通过分析粗、细尾砂料浆的塌落度和流变试验结果,发现料浆塌落度与屈服应力之间呈指数关系。     

高浓度聚合物驱所用聚合物性能研究

针对喇嘛甸油田高浓度聚合物驱所用聚合物,利用PHYSICA MCR300型流变仪研究了其浓度、分子量及矿化度对溶液流变性和黏弹性的影响。结果表明:在一定范围内,聚合物溶液的表观黏度随着剪切速率的增加而降低,表现出假塑性流体的特性。聚合物浓度、分子量增大时,溶液的表观黏度、储存模量和损耗模量均增大;相应的储存模量和损耗模量曲线都有一个交点。所对应的角频率随聚合物浓度、分子量增大而减小。水质对聚合物溶液性能有较大影响。随着矿化度的增大,溶液的表观黏度、储存模量和损耗模量均减小,储存模量和损耗模量曲线的交点所对应的角频率增大。     

聚对苯二甲酸乙二醇酯的流变性能研究

利用ＸＬＹ－２型毛细管流变仪研究了聚对苯二甲酸乙二醇酯（ＰＥＴ）的流变性能,讨论了剪切速率、剪切应力和温度对ＰＥＴ熔体表观粘度的影响。结果表明：ＰＥＴ熔体的表观粘度随着温度的升高而降低;粘流活化能（ΔＥ）随着剪切速率的增大而减小,在实验温度下,ＰＥＴ熔体的表观粘度随剪切速率和剪切应力的增大而降低,非牛顿指数小于１,ＰＥＴ熔体为假塑性流体。     

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.     

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.     

The Analects and the Moment in Peking——The influence of a Confucian education system on the personality formation,the way of thinking and the fate of the main characters

0.Preface China has long been boasting of its colorful and immense culture which comprises of Taoism,Confucianism and Buddhism.The interwoven influence among the religions on Chinese way of thinking,on the nation＇s behavior in their social life throughout the long history is beyond list.