变黏酸的基本原理及发展概况

阐述了目前油田现场使用过的三种变黏酸（聚合物温控变黏酸、聚合物pH值控制变黏酸、黏弹性表面活性剂pH值控制变黏酸）的基本原理及发展概况.并通过分析三种变黏酸存在的缺陷,提出了变黏酸今后的研究方向.     

冷却塔蒸发损失水量计算方法探讨

冷却塔蒸发损失水量计算目前多采用估算法,也有采用理论计算法的,且不同的设计规范提出的要求不尽相同,因此在工程项目设计计算蒸发损失水量时,对该问题的认识一直比较混乱。针对这种现状,通过对南方湿热地区和北方干热地区2个典型地区采用不同计算方法的比较分析,提出工程项目在可行性研究阶段可采用估算法计算冷却塔蒸发损失水量,而在总体设计及以后阶段采用理论计算法。这种分阶段采用不同方法计算冷却塔蒸发损失水量的方法,不仅满足了工程项目的设计要求,同时,还减少了项目投资,降低了水资源使用量。     

一种提高焦化加热炉热效率方法的经济性分析

焦化加热炉的燃料消耗在焦化装置能耗中占有很大的比例,提高焦化炉的热效率,减少燃料消耗,能够达到加热炉节能减排的目的。通过降低焦化加热炉外壁温度减少炉体散热损失是已知有效地提高加热炉热效率方法之一,然而减少炉壁散热损失就意味着增加投资,那么炉壁温度降低到什么程度最为合理,以国内常用的典型焦化炉炉型和应用了较为先进的附墙燃烧技术的炉型为例,以这两种炉型常用的衬里材料为参考依据,通过计算几种不同外壁温度下两种炉型的散热量和衬里用量的变化,进行了相应的经济性计算分析,结果显示在现行设计标准的基础上降低炉墙外壁温度,可以有效减少散热损失,进而提高焦化炉热效率是可行的,在多个炉墙外壁温度的比选中,以三年投资回收期来看,60℃的外壁温度最为经济合理。     

7500T大型压铸机增压阀块内流道流场仿真分析及优化

设计性能优良的阀块对提升液压系统性能具有重要意义。利用计算动力学方法对7500T大型压铸机增压阀块的流阻特性进行分析,计算得到两种不同压铸机增压阀块结构在不同流量时的压力损失。结果表明：增压阀块压力损失随着流量的增大呈现出近似线性增大的变化情况;加设倾斜流道的压力损失比没有倾斜流道的压力损失小,且减阻效果随着流量的增大而增大。利用正交试验建立了4因素5水平的正交试验数据库,对斜流道增压阀进行多参数单目标优化,然后基于遗传算法协同BP神经网络优化斜流道增压阀块之后,可使增压阀块的压力损失下降20%左右。     

Sn含量对Zr-Sn-0.2Fe-0.1Cr合金高温蒸气氧化行为的影响

锆合金的高温蒸气氧化行为是失水事故下需要重点关注的问题之一。为了研究Sn对锆合金高温蒸气氧化行为的影响,开展了不同Sn含量的SH12(Zr-0.75Sn-0.2Fe-0.1Cr,质量分数,%)和Zr-4(Zr-1.5Sn-0.2Fe-0.1Cr)合金在模拟失水事故工况下1000、1050、1100和1200℃的高温蒸气氧化试验。采用光学显微镜、电子探针、显微硬度计分析了氧化样品的显微组织以及氧化前后样品的显微硬度。结果表明：低Sn的SH12比高Sn的Zr-4合金的抗高温蒸气氧化性能更好,这说明降低Sn含量可以改善锆合金的抗高温蒸气氧化性能。氧化前,SH12合金的显微硬度低于Zr-4合金,而氧化后SH12合金基体的显微硬度明显高于Zr-4合金,与氧化后SH12合金基体中的氧含量高于Zr-4合金的结果相吻合,这说明Sn有抑制氧在Zr基体中扩散的作用。通过第一性原理计算,发现Sn容易与O结合,从而抑制了O在锆基体中的扩散,这合理解释了氧化后SH12合金中的氧含量比Zr-4合金高的原因。     

Particle loss: An initial investigation into size effects and stress-dilatancy

Drained triaxial tests have been performed to explore the effect of particle loss on shearing behaviour and critical states in granular mixtures. The mixtures comprise Leighton Buzzard sand (d₅₀ = 0.8 mm), to which was added 15% by mass of salt particles of different nominal sizes: 0.063 mm, 0.25 mm and 0.5 mm. Shearing behaviours before and after particle loss (by dissolution) were compared. A good fit is observed between the test data and a stress-dilatancy relationship for the post-dissolution tests, highlighting the ability of the stress-dilatancy analysis as a means to interpret the effects of particle loss on shearing. It was noted that critical state strength parameter M is determined by the post-dissolution grading regardless of size of removed particle. However, the duration of contractant volumetric strain increased with the larger removed particles (0.25 mm & 0.5 mm) even when initial specific volumes were virtually identical. It is suggested that a loose volumetric state is reached if the sand particle network is initially disrupted by the amount and/or size of salt particles, which following dissolution results in structural or fabric phenomena that are not reflected in scalar volumetric measures such as specific volume.     

Influence of Diet,Menstruation and Genetic Factors on Iron Status: A Cross-Sectional Study in Spanish Women of Childbearing Age

The aim of this study was to investigate the combined influence of diet, menstruation and genetic factors on iron status in Spanish menstruating women (n = 142). Dietary intake was assessed by a 72-h detailed dietary report and menstrual blood loss by a questionnaire, to determine a Menstrual Blood Loss Coefficient (MBLC). Five selected SNPs were genotyped: rs3811647, rs1799852 (Tf gene); rs1375515 (CACNA2D3 gene); and rs1800562 and rs1799945 (HFE gene, mutations C282Y and H63D, respectively). Iron biomarkers were determined and cluster analysis was performed. Differences among clusters in dietary intake, menstrual blood loss parameters and genotype frequencies distribution were studied. A categorical regression was performed to identify factors associated with cluster belonging. Three clusters were identified: women with poor iron status close to developing iron deficiency anemia (Cluster 1, n = 26); women with mild iron deficiency (Cluster 2, n = 59) and women with normal iron status (Cluster 3, n = 57). Three independent factors, red meat consumption, MBLC and mutation C282Y, were included in the model that better explained cluster belonging (R² = 0.142, p < 0.001). In conclusion, the combination of high red meat consumption, low menstrual blood loss and the HFE C282Y mutation may protect from iron deficiency in women of childbearing age. These findings could be useful to implement adequate strategies to prevent iron deficiency anemia.     

新型聚合物型水基钻井液降失水剂的合成及性能研究

以烯丙基磺酸钠(AS)、甲基丙烯酸甲酯(MA)、丙烯酰胺(AM)为原料,合成了一种新型聚合物型水基钻井液降失水剂。降失水剂的最佳合成条件为:反应温度65℃,引发剂用量0.35%,单体总浓度30%,pH=7,单体配比AM∶AS∶MA=35∶15∶50。该降失水剂具有良好的降失水效果,且对钻井液的流变性影响不大。