石油化工泵备用机械密封及报警系统的研究

为防止和监控关系泵用机械密封的突然失效，研制了备用机械密封及提警系统，该系统是在主密封后面安装一个非接触式备用机械密封，主密封与备用密封间有一个辅助密封腔，与压力报警装置相连，当主密封失效时，辅助密封腔内压力上升，驱动备用密封的两端面立即贴合进入工作状态，起到二次密封的作用，阻止危险介质向大气泄漏保证主机连续运转，此系统比传统的双端面密封及串联密封的结构简单，安装方便，给出了非接触式备用机械密封的     

石油化工泵备用机械密封及报警系统的研究

为防止和监控关键泵用机械密封的突然失效，研制了备用机械密封及报答系统。该系统是在主密封后面安装一个非接触式备用机械密封，主密封与备用密封间有一个辅助密封腔，与压力报警装置相连。当主密封失效时，辅助密封腔内压力上升，驱动备用密封的两端面立即贴合进入工作状态，起到二次密封的作用，防止危险介质向大气泄漏并保证主机连续运转。此系统比传统的双端面密封及串联密封的结构简单，安装方便，给出了非接触式备用机械密封的设计方法和计算公式，得出了备用密封的最佳参数范围。试验及现场检验表明，研制的备用密封工作多数在理论上与实际相一致。     

冷媒泵轴断裂失效原因分析

针对冷媒泵轴在安装运行过程中短期内发生多次断裂事故,采用光学显微镜、X线荧光光谱仪、扫描电镜断口分析、能谱分析等手段,对其进行断裂失效分析。结果表明:冷媒泵轴材质成分符合标准要求,断口裂纹源呈典型的氢脆(氢致腐蚀)特征,断裂应为氢脆引起的快速开裂。     

60Si2CrVA圆柱弹簧断裂失效的原因分析

对某电梯锁紧用60Si2CrVA圆柱弹簧在安装调试过程中出现的失效断裂,结合弹簧制造的生产过程,采用原子吸收光谱、断口电镜扫描、金相检验等方法对失效断口进行了详细分析,发现可能导致该弹簧失效的几种缺陷:原材料化学成分不均匀、内部结构存在缩松、缩孔以及热处理工艺不当等,并分析这些缺陷对弹簧性能及弹簧失效造成的影响.     

进口糊树脂单体泵机械密封失效分析及改造

针对进口糊树脂单体泵在特定使用工况条件下所造成的机械密封失效进行分析,提出了机械密封的改造方案,改进了弹簧的形式并采用浮装结构,解决了机械密封的短期失效问题。     

环管反应器轴流泵机械密封消除冲洗死区改造

茂名高密度装置反应器轴流泵机械密封出现损坏,进行查找原因,确认是机械密封存在冲洗死区,冲洗异丁烷气化后进入密封油系统,污染密封油,造成密封损坏。对机械密封进行改造,消除冲洗死区。     

发动机支架安装凸台的断裂故障诊断分析

针对发动机发电机支架安装凸台及连接螺栓常出现的断裂失效问题,提出一种仿真分析与实验结合的诊断方法.首先建立了包含发电机和空压机模型的支架有限元模型,并进行了约束模态分析,进而针对缸体局部和电机支架进行了螺栓预紧应力分析.最后,对发电机和空压机进行了动平衡测试.仿真与试验结果表明:发动机运行期间,连接区域松脱可能是造成失效的重要原因.采用该诊断方法解决了失效问题.     

皮带机尾托带滚筒改造方式

由于主运输皮带的运输煤量载荷比较重,皮带的运输距离比较远,皮带运转时间比较长,造成皮带机尾的托带滚筒容易顺坏,这就直接影响了主运输系统的安全性和可靠性。托带滚筒损坏造成的事故影响时间较长,究其原因分析为滚筒重量较重,运输距离较远,现场更换比较困难。文章对皮带机尾托带滚筒改造方式进行了探讨。     

富水粉细砂层盾构下穿湖泊风险分析及控制——以太原地铁2号线下穿迎泽湖工程为例

太原地铁2号线盾构隧道采用土压平衡盾构施工方式,盾构区间按照设计需要下穿湖泊穿越富水粉细砂层。为了保证盾构施工安全平稳通过,合理控制土压平衡盾构下穿湖泊的风险源,对风险产生的机理和如何控制风险进行了研究。分析了盾构穿越富水粉细砂层主要风险:含水地层盾构螺旋机喷涌机理,盾构通过后盾尾空隙沉降较大原因,盾尾密封失效风险。针对风险控制提出包括调整渣土改良参数,优化同步注浆配比,对盾构机尾刷改造等措施。工程实践表明,在富水粉细砂层中掘进,将高分子聚合物浓度创新性地提高到10/1 000,可以有效控制螺旋机喷涌,降低盾构下穿湖泊时湖底坍塌、湖水倒灌风险;通过将第三道盾尾刷由钢丝尾刷改造为钢板尾刷,有效减小了盾尾刷磨损导致盾尾密封失效风险;优化盾构掘进过程中同步注浆浆液的配比,使其凝固时间由6 h变为4 h,有效控制了盾构通过后的盾尾空隙沉降过大风险,最终湖底监测点测得累计沉降25.33 mm,取得了较好的施工效果。     

油田泵类设备机械密封腐蚀失效分析

泵类设备在油田广泛使用,其结构设计常采用机械密封。在使用过程中,如果机械密封失效,轻则泄漏,重则设备的运转率急剧下降或造成设备的运转故障,严重的还会造成设备事故。分析了泵类设备机械密封腐蚀失效的原因和特征,对密封件腐蚀失效进行了分类,并列举了一些工程腐蚀失效实例,提出了泵类设备机械密封抗腐蚀的具体技术措施。     

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.     

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.     

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.