薄形铜冷却壁的热态实验分析

为了减少高炉冷却壁的铜消耗量,降低单个铜冷却壁的价格,在保证高炉冷却效果的基础上,开发了一种薄型的铜冷却壁.为了测定该薄形铜冷却壁的冷却性能,设计了热态实验进行模拟实验.在未挂渣的情况下,当炉温为1200℃时,冷却壁冷面和热面的平均温度分别为72℃和135℃.当有热冲击的情况下,冷却壁冷面和热面的温度差变化不大.加快流速对降低冷却壁温度影响不大.当热面挂渣时,冷却壁的热流密度急剧降低,而且冷却壁热面温度随炉温变化很小.经过热态实验,薄型铜冷却壁的温度分布和热流密度基本符合高炉实际生产要求.     

混合电动车用MH/Ni电池组热效应仿真及应用研究

对MH/Ni电池组(结构A)的充电热效应进行了分析,采用FLUENT软件模拟的方法,研究了两种新型MH/Ni电池组结构(结构B和C)热管理的通风冷却效果.根据计算,分析了流动回流因素对温度场的影响,并提出了结构改进建议.热管理系统C型在电池组充放电试验中的结果表明:8 A充电时电池组内温度升高小于5℃,温度差异小于4℃,系统冷却效果良好.     

电主轴轴心冷却用环路热虹吸管的传热特性

为了加强电主轴轴心冷却、减小电主轴的热变形,以150SD型磨削电主轴转子为对象,采用单环路热虹吸管来冷却主轴轴心,利用环路热虹吸管无需外部动力及传热效率极高的特征,从原理上避免了"动密封"问题对电主轴轴心冷却的困扰。对高离心力作用下单环路热虹吸管内传热工质的流动及传热状态进行了理论分析;以正戊烷为工质,对适用于该主轴轴心冷却尺寸的环路热虹吸管的传热特性进行了实验研究,并对其应用于电主轴轴心冷却的实际效果进行了预测。结果显示:在文中的实验工况下,单环路热虹吸管的运行温度稳定,其传热性能在充液率为60%左右时达到最佳,热阻仅为0.57℃/W;当采用4根单环路热虹吸管冷却结构时,150SD型磨削电主轴转子的最大温升为28.5℃,且这一温升数值随着转速的增加而继续减小,表明单环路热虹吸管在电主轴轴心冷却方面具有良好的应用效果。     

电动汽车锂电池模块化热管理系统的设计及实验研究

针对电动汽车锂电池在高温情况下极易引发电池的性能退化,甚至导致热失控的问题,提出了一种电动汽车锂电池模块化热管理系统设计方案。所设计的系统采用20节圆柱形电池交错排列方式,电池之间布置6块内含冷却液流道的冷却单体,利用冷却单体中流动的冷却液迅速带走电池在工作时产生的热量,保证锂电池工作在25～40℃的适宜范围内。采用所设计系统针对冷却液流速、管道连接方式对电池模组冷却性能的影响进行仿真与优化,并根据优化结果,搭建实验平台进行实验验证。实验结果表明:增大冷却液流量可有效提高冷却效率,但流量的选取应权衡冷却效果与消耗功率的利弊;电池并联的最高温度和温差比串联分别下降了7.55℃和6.74℃,说明并联对提高整个模块化电池热管理系统的散热性能具有较好的效果,在电池包数量较大时,宜采用并联方式;并联缩短了温度大范围波动的时间,减小了过大的温度波动对电池造成的影响。     

热冲击作用下花岗岩渗透性演变规律试验研究

为研究高温花岗岩在热冲击作用下渗透性能变化规律,对不同温度花岗岩试件在空气中自然冷却、在水中(20℃,60℃,100℃)热冲击冷却等4种冷却条件下的渗透率变化规律进行分析,借助热冲击因子对不同冷却温度的热冲击破坏进行定量表征,研究结果表明:热冲击作用下试件渗透率增加幅度与岩石温度的升高呈指数关系;冷却介质与高温岩石之间的温差和对流换热系数共同影响热冲击过程中热量交换的速率,进而影响到热冲击破坏的结果;热冲击因子可以作为衡量热冲击破坏能力的物理量,热冲击破坏后花岗岩的渗透率随热冲击因子单调增加且存在阈值,超过阈值后试件渗透率随热冲击因子的增加而大幅度增加。     

热轧低碳钢卷取后冷却过程中三次氧化铁皮结构转变行为

采用SEM和热模拟试验机研究在卷取后连续冷却条件下、不同的卷取温度和不同冷却速度条件下低碳钢三次氧化铁皮结构转变行为。研究结果表明:在连续冷却转变过程中,FeO层的转变均遵循"C"曲线规律,400~500℃为FeO共析反应的"鼻温"范围,在这个温度区间内,以较小的冷速冷却到室温可以得到以共析组织Fe3O4和单质Fe为主的氧化铁皮结构,较快冷速则会抑制共析反应的发生;当冷速达到25℃/min时,FeO共析转变进程被抑制,氧化铁皮结构以先共析Fe3O4为主。结合连续冷却结构转变曲线,通过控制卷取温度和冷却速率,可以控制FeO的共析反应进程,从而达到精确控制氧化铁皮结构目的。     

新能源汽车锂电池热管理系统热性能分析与优化控制研究

为了提高新能源汽车锂电池的使用寿命和性能,本研究通过仿真、试验对新能源汽车锂电池的热管理系统进行了分析。首先建立了锂电池组和冷却结构的计算模型,然后设计了锂电池热管理系统,在此基础上,对锂电池热管理系统冷却结构进行了优化,最后,分析了计算模型的仿真结果和热管理系统冷却结构散热性能仿真结果。影响锂电池热管理系统散热的因素包括冷却液流量、冷却液入口温度和放电倍率。结果表明,本研究所建立的计算模型是可行的,当确定了最优结构、冷却液流量值、冷却液入口温度和放电倍率时,在最优参数下,锂电池热管理系统具有良好的冷却效果,研究结果可为新能源汽车的热管理和散热技术提供坚实的理论基础。     

基于热-流-固耦合的航空发动机尾气采样装置设计

为满足当前国际社会对于航空发动机排气污染物的严格要求,需要在航空发动机高温、高速尾流场中采集排气污染物并进行组分浓度测量。在使用地面试车台开展某新型低冰点燃料尾气排放特性测量试验时,针对所用发动机排气温度较高的问题,设计了三种带水冷的尾气采样装置方案,并通过热-流-固耦合方法对三种方案的冷却效果和结构强度进行分析。计算结果表明,冷却水进口压力为0.3 MPa时,方案1采样装置表面最高温度超过1600 K,冷却效果无法满足设计要求;方案2采样装置最高温度约840 K,方案3最高温度约1240 K,冷却效果均能满足要求。对方案3进行静强度分析,其静强度安全系数为3.34,具有足够的安全裕度。使用所设计的采样装置成功完成该型燃料尾气成分测量试验,验证了所采用的设计方法的可靠性,可以为提高现有尾气采样装置设计能力提供参考。     

高温后高强沙漠砂混凝土力学性能研究

为了研究高强沙漠砂混凝土高温后的力学性能,采用室温、200℃,400℃,600℃,800℃和900℃六个温度等级,利用自然冷却方式,通过正交试验,研究水胶比,粉煤灰掺量和沙漠砂替代率对高强沙漠砂混凝土高温后抗压强度的影响,对高强沙漠砂混凝土试件高温后的外观颜色变化进行了观察,分析了高温后高强沙漠砂混凝土试件的质量变化。试验研究表明:与室温下高强沙漠砂混凝土抗压强度相比,200℃高温后高强沙漠砂混凝土强度有所降低,在400℃至600℃高温后抗压强度有所升高,之后随着温度的升高抗压强度逐渐降低;随着温度升高,高强沙漠砂混凝土外观颜色由深变浅,质量损失率呈现逐渐增加趋势。通过方差分析和极差分析,给出了高强沙漠砂混凝土最佳配合比,为高强沙漠砂混凝土的工程应用提供借鉴和指导。     

轴向通风永磁同步电机三维热网络模型

轴向通风电机中的冷却介质存在温差,直接影响电机的温度场分布.针对这一问题,建立了轴向通风永磁同步电机中冷却气流的数学模型,并与永磁同步电机本体结构的热网络模型相结合,构建了整体三维热网络模型.建立了描述导纳矩阵、网络节点温度、冷却气流温度之间关系的节点方程,得到了轴向非对称的温度分布,克服了传统T型网络法的不足.运用有限元软件进行流体场和温度场的耦合仿真,对比两者得出的温度值,证实了该三维热网络模型的可行性.     

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。     

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.