脉冲气力输送——一种粉粒料低速高浓度密相输送的新技术

粉粒料的散装输送,大体上可分为机械输送和气力输送两大类。气力输送是利用气流实现粉粒料的管道输送。若按混合比(每公斤气体所能送走多少公斤的物料量)来分,一般认为在5以下的为稀相气力输送,5以上的为密相气力输送。近年来,随着密相输送技术的新进展,在密相输送中,又按其物料移动速度的高低和混合比的大小,将其分为一般的密相输送和低速(一般速度为5米/秒以下)、高浓度(混合比大于40)     

国省干线公路沥青路面坑槽病害的成因及修补工艺

坑槽是沥青路面种类破损中常出现且危害性较大的一类破损。特别是在降雨后或在冬春季之交雪水的反复冻融后会产生大量的坑槽破损。如果不得到良好的修补,其蔓延速度之快、恶化程度之深,因此必须及时处理并保证维修质量。本文根据沥青路面坑槽修补的最终目的,分析沥青路面出现坑槽的原因和修补工艺,使之能达到理想的维修效果。     

浅谈沥青混凝土路面坑槽的修补

本文根据沥青混凝土路面坑槽修补的最终目的和效果,介绍了坑槽修补常用的施工工艺,对修补材料提出要求,并对坑槽修补各施工工艺在修补效果和造价经济上进行了比较.     

基于正交试验设计的水合物浆液流动特性数值模拟

 针对竖直管道内水合物浆液输送过程中的流动问题,以浆液流速、水合物颗粒粒径和水合物颗粒体积分数作为影响浆液流动特性的主要因素,以水合物浆液在管道输送过程中的压降为评价指标,对水合物浆液在竖直弯管中的流动进行了正交试验设计,并在正交试验设计的基础上运用CFD软件模拟了浆液在管道中的流动情况。结果表明,在浆液输送过程中,输送速度对压降的影响最大,随着输送速度的增加,压降损失也随之增大;颗粒的粒径对压降的影响次之,水合物颗粒的粒径越小对压降的影响越大,随着粒径的增大,压降损失趋于平缓;水合物颗粒体积分数对压降的影响最小,随着水合物颗粒体积分数的增加,压降逐渐减小。通过对试验结果的进一步分析,给出了该试验条件下水合物浆液在管道输送较优的方案。     

沥青路面坑槽修复材料研发及结构力学响应分析

目的研发一种新型高性能沥青路面坑槽修复材料,探究坑槽修补面积、修补厚度对修补后路面结构的影响.方法通过挥发速率试验确定稀释剂.通过马歇尔稳定度试验确定添加剂.并对混合料进行马歇尔稳定度试验、高温稳定性试验、水稳定性试验等路用性能试验.利用ABAQUS建立沥青路面坑槽修补有限元模型,分析不同修补面积、不同修补厚度对路面结构修补的影响.结果稀释剂B与添加剂c为最优组合.当稀释剂B掺量为20%,添加剂c掺量为10%时,其初始强度达到4.03 kN,成型强度达到6.93 kN,施工和易性好,水稳定性试验中马歇尔残留稳定度大于75%,冻融劈裂强度比大于70%,车辙试验中动稳定度1 487次/mm.剪应力的最大值出现于坑槽底部,拉应力的最大值出现于轮隙中心,压应力的最大值出现于坑槽表面.随着修补面积和修补厚度的增加,最大压应力和拉应力随之增加,最大剪应力随之减小.结论研发的沥青路面坑槽修复材料性能良好,满足《公路沥青路面施工技术规范》(JTG F40—2004)与工程使用要求.在坑槽修补的底部、表面应力最大值处,应保证混合料的密实性与原有路面的黏结性.以确保不产生二次破坏.     

旋流纺输送管道不同进口角度的流场数值仿真

旋流纺输送管道的进口面与顶面和底面形成的角度是影响输送管道内气流运动的重要因素之一,为了通过合理配置输送管道进口面各角度来减小输送管道结构对输送管道内气流运动的阻碍,采用计算流体力学方法建立了输送管道仿真模型,对圆盘式旋流纺纱输送管道内部气流场进行了数值仿真.分别以3种不同角度为例,得出了不同角度对输送管道内部气流场的气流模式的影响.仿真结果表明旋流纺输送管道内气流分布与进口面各角度的配置关系复杂,随各角度的变化,气流分布会有很大变化.     

气—固相悬浮运动及输送管径计算的修正

输送管径的计算与气一固相的运动特征有关。本文首先对固相质点和粒子群的运动形式作了分类。固相质点运动时沿管道断面的分布状态,主要决定于气流紊流的性质与作用。根据普朗特理论,质点的分布状态可描述为关系式n=n_1(y/y_1)~(-V_0/(βV_*))。由于固相质点的影响,气流速度沿水平管道断面不再作对称分布;但气流速度沿垂直管道断面却作双对数曲线对称分布。考虑固相质点的影响,对稀相输送的输送管径通用计算公式D=(4Q气/4U气)~(1/2)进行修正,得出修正后计算公式为为修正系数。在度浓比超过10时,建议采用修正后计算公式求输送管直径。     

动荷载与温度场作用下沥青路面坑槽修补界面力学特性研究

针对沥青路面坑槽修补后接缝破损现象突出问题,利用有限元软件建立沥青路面坑槽的三维有限元模型,分析了半波正弦荷载与移动均布荷载作用下坑槽修补界面的应力变化规律,并计算了周期性变温条件下坑槽修补界面的温度场与应力场的分布规律。研究结果表明：沥青路面坑槽修补界面主要受压和受剪,拉压应力交替变化的波形是使路面修补区域产生破坏的主要因素;修补区域路表由于温度应力的影响,很容易造成接缝开裂和向下延伸的趋势,且日温差越大沥青路面修补区域界面的温度应力也越大。     

基于水晶棉纤杂不同沉降性能设计的分离管道的数值模拟

建立三维计算流体力学(CFD)模型,对所设计管道内的气流状态进行三维数值模拟,将模拟结果与沉降差异相结合,通过理论计算验证了管道纤杂分离的可行性.并对水平管道长度、弯道角度、转弯弧度及出口宽度这4个管道结构参数分别进行调整后模拟.研究结果表明:增加水平管道长度能提高纤杂输送速度及分层效果;增加弯道角度能使纤维收集速度增大;转弯弧度和出口宽度对纤维收集速度的影响大于对纤杂输送速度的影响,因此,需调整转弯弧度使纤杂输送速度提高的同时又不破坏收集气流的稳定性,并适当减小出口宽度以提高纤维的收集速度.     

浅议沥青混凝土路面坑槽修补分析

坑槽是沥青混凝土路面种类破损中较常出现且危害性较大的一类严重破损。特别是在降雨后或在冬春季之交雪水的反复冻融后．会产生大量的坑槽破损。沥青混凝土路面出现坑槽破损不仅严重影响路面的平整度和行车的舒适性，而且若不及时对坑槽进行修补在交通荷栽作用下其路面破损面会逐渐扩大、加深并连成一片．造成维修费用的急剧增多并危机乘车人员的生命安全。根据沥青混凝土路面坑槽修补的最终目的以及坑槽修补材料的受力状况．分析研究出了沥青混凝土路面坑槽的修补机理，提出了获得理想维修效果的具体要求。     

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.     

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。     

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.     

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.