油田水中部分水解聚丙烯酰胺浓度的检测技术优化

随着油田的不断开发,二连油田进入大面积的三次采油技术,在驱油过程中,经常要测定产出液中的聚丙烯酰胺的浓度,以判断驱油过程中聚合物溶液的流动、降解情况。目前,二连油田对产出液中聚丙烯酰胺浓度的检测方法主要是采用淀粉—碘化钾分光光度法,该方法的原理是:由于聚丙烯酰胺     

用UV-VIS分光光度计测定荧光增白剂CXT强度的新方法

本文通过对荧光增白剂CXT溶解方法的研究和对其λmax参比溶液及样品溶液浓度的选择,确定了一种用UV-VIS分光光度计测定荧光增白剂CXT强度的新方法.     

聚间苯二甲酰对苯二胺(PPIA)数均分子量的测定

聚间苯二甲酰对苯二胺是一种新型的芳酰胺聚合物,极有潜力发展为高性能纤维家族的新成员。由于聚间苯二甲酰对苯二胺分子链的刚性特征,使得现有凝胶渗透色谱(GPC)仪器所用的溶剂很难对其溶解,其分子量的测定不能采用凝胶渗透色谱的方法,因此采用端基分析法测定聚间苯二甲酰对苯二胺的数均分子量。采用直接电位滴定法测定聚合物羧端基的含量,以玻璃电极做指示电极,甘汞电极为参比电极,用电位滴定仪进行测定。采取分光光度法测定聚合物的氨端基含量,利用分光光度计测定不同浓度对苯二胺溶液的吸光值,绘制出浓度-吸光值曲线,然后用已知浓度的对氯苯胺溶液进行校验,最后测定聚合物溶液的吸光值可算出氨端基含量。最后结合端羧基和端氨基的含量通过计算得到聚间苯二甲酰对苯二胺的数均分子量,此方法简单、实用,不需要复杂的仪器设备。     

油田用防垢剂性能评定探索研究

对石油天然气行业标准SY/T 5673—93"油田用防垢剂性能评定方法"中防垢剂对硫酸钡、硫酸锶垢防垢性能评价的相关实验进行探索研究,对标准中的一些实验步骤进行改进,得到可以对硫酸钡垢、硫酸锶垢进行较为精确且实际的性能评定方法。防垢剂选为聚环氧琥珀酸,使用UNICAM 969 AA原子吸收分光光度计进行钡离子和锶离子的测定,其中钡离子标样溶液浓度选择为0.25,0.50,1.00 g/L,锶离子标样溶液浓度为0.01,0.03,0.05 mg/L。     

UV法和HPLC法测定合成色素诱惑红的比较

比较检测糖果中合成色素诱惑红的两种方法。用聚酰胺粉吸附提取诱惑红色素,再分别用纸色谱法分离紫外可见分光光度计法测定和反相高效液相色谱法分离测定外标法定量。高效液相色谱法的精密度高于紫外可见分光光度计法,高效液相色谱法的检出限低于紫外可见分光光度计法。测定糖果中合成色素诱惑红含量时,高效液相色谱法优于紫外可见分光光度计法。     

聚丙烯酰胺产品中尿素含量的测定

建立了聚丙烯酰胺中尿素的测定方法。用亚铁氰化钾和乙酸锌将样品中的聚丙烯酰胺沉淀后,滤液中的尿素与4-二甲基氨基苯醛(4-DMAB)显色剂反应生成黄色物质,用分光光度法对尿素含量进行测定。合成了一系列不同含量尿素的聚丙烯酰胺样品,精密度和回收率实验显示,6次测定结果的RSD3%,相对测量误差均≤4.73%。方法简便、快速,为聚丙烯酰胺的质量控制提供了一种准确可靠的检测方法。     

新型温敏改性丙烯酰胺共聚物的性能研究

以2,2,3,4,4,4-六氟甲基丙烯酸酯(AF6)和丙烯酸辛烷基酚聚氧乙烯酯(OPA7)为共聚单体改性聚丙烯酰胺(PAM),得到P(AM-AF6)、P(AM-OPA7)和P(AM-OPA7-AF6)三种共聚物,其中P(AM-OPA7-AF6)溶液表现良好的热增稠性。采用可见分光光度计、动态光散射(DLS)和荧光分光光度计研究了三种共聚物分子在溶液中的相互作用。结果表明:P(AM-AF6)和P(AM-OPA7)溶液在30～85℃未产生疏水缔合,高温增稠现象不明显。对于P(AM-OPA7-AF6)聚合物,单体AF6与OPA7中的氟碳链与聚乙烯醚链在升温过程中的协同作用极大地影响了聚合物分子的自组装行为,诱发了溶液-凝胶转变行为,明显提高了其盐溶液表观黏度。     

用原子吸收分光光度计测定麦芽酚含量

原子吸收分光光度计和紫外分光光度计在原理和结构上有很多相似之处 ,因此在一定条件下可以用原子吸收分光光度计代替紫外分光光度计进行测定     

用原子吸收分光光度法测定麦芽酚含量

原子吸收分光光度计和紫外分光光度计在原理和结构上有很多相似之处,因此在一定条件下可以用原子吸收分光光度计替代紫外分光光度计进行测定。     

分光光度法测定铝合金中低含量的铋

采用分光光度法建立一种测定铝合金中低含量铋的测定方法,此法测量范围在0.05%～1%,样品经碱溶、酸化后得到澄清溶液,加入硫脲及碘化钾显色,在464 nm波长下用分光光度计测定浓度在0.1～1 mg/m L对应的吸光度,符合朗伯-比尔定律,线性回归方程为y=0.0544x-0.0019,相关系数R2=0.9998,加标回收率在92.8%～104.9%,该方法快速、准确,适用于铝合金中低含量铋的测定。     

底座连接口特征参数对显示器后壳注塑质量的影响分析

在Moldflow分析软件的基础上,对显示器后壳进行仿真研究,以翘曲变形量为质量指标,结合控制变量法进行单因素变动实验,保持注射工艺参数不变,研究显示器后壳底座连接口对制品翘曲变形的影响.对数据进行图表分析,结果表明显示器后壳尺寸定位68.58 cm(27英寸)时,底座连接口选用圆形,连接口位置距离底边26 mm,尺寸...     

The role of the symmetry and the flexibility of the anion on the characteristics of the nanostructures and the viscosities of ionic liquids☆

The transport properties of ionic liquids (ILs) are crucial properties in view of their applications in electrochem-ical devices. One of the most important advantages of ILs is that their chemical–physical properties and conse-quently their bulk performances can be well tuned by optimizing the chemical structures of their ions. This will require elucidating the structural features of the ions that fundamentally determine the characteristics of the nanostructures and the viscosities of ILs. Here we showed for the first time that the“rigidity”, the order, and the compactness of the three-dimensional ionic networks generated by the anions and the cation head groups determine the formation and the sizes of the nanostructures in the apolar domains of ILs. We also found that the properties of ionic networks are governed by the conformational flexibility and the symmetry of the anion and/or the cation head group. The thermal stability of the nanostructures of ILs was shown to be con-trolled by the sensitivity of the conformational equilibrium of the anion to the change of temperature. We showed that the viscosity of ILs is strongly related to the symmetry and the flexibility of the constitute ions rather than to the size of the nanostructures of ILs. Therefore, the characteristics of the nanostructures and the viscosities of ILs, especially the thermal stability of the nanostructures, can be fine-tuned by tailoring the symmetry and the conformational flexibility of the anion.     

浅谈设备的性能与操作对胎面压出质量的影响

简要介绍了胎面压出的工作原理及工艺过程，对设备的配置及操作对胎面压出质量的影响进行了分析，并对压出过程中常见的质量缺陷、造成的原因以及解决措施提出了自己的见解。     

Investigation of the effects of fatty acids on the compressive strength of the concrete and the grindability of the cement

In cement industry, a great energy consumption has been observed during grinding of clinker. To reduce this consumption, some waste products have been used as grinding aids.In this investigation, the effects of sunflower oil (SO), oleic acid (OA), stearic acid (SA), myristic acid (MA) and lauric acid (LA) on the fineness and strength of the cement have been examined. These aids were added into clinker in certain ratios based on the cement clinker weight and the grinding has been done for a definite time at the same condition.All of the fatty acids used increased the fineness as compared with the cement without the grinding additives. SO and OA decreased the strength significantly, LA decreased it to a lesser extent and SA increased it definitely according to the common cement. But MA did not alter the strength of the cement as much as SA. In addition, the covering of the balls influences the grinding of cement clinker unfavourably.     

煤粉流动性对GSP气化炉气力输送的影响研究

针对GSP气化装置煤粉气力输送在试车阶段出现的煤粉锁斗下料不畅、发料罐输送性能不佳等问题,从原料煤性质和工业装置的改进方面出发,通过煤粉的流动性参数的测量与研究,分析出现上述工程问题可能的内在原因,并提出工业装置改进方法,为保证GSP煤粉气力输送工业装置的正常运行提供解决办法。     

关于建立火炸药安全数据库的探讨

由反映火炸药及其制品的危险性能和用于对它们的生产、储运系统进行安全评价数学模型出发,探讨了如何建立一个全面、实用的火炸药安全评估数据库。通过对此数据库内容、数据表示方法、数据搜索方法以及建立步骤的讨论,明确了该数据库的使用对象和主要功能。     

The effect of the length of the oxyethylene chain on the conductivity of the polyurethaneurea electrolyte

Polyurethaneureas (PUU), which were synthesized from 4,4′-diphenylmethane diisocyanate (MDI), poly(ethylene glycol) (PEG), and 3,5-diaminobanzoic acid (DABA), were used as polyelectrolytes in this study. Differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FT-IR) were used to monitor the effect of the various kinds of PEG on the changes in morphology of PUU electrolytes corresponding to the concentration of lithium perchlorate (LiClO₄) dopants. The results of DSC and FT-IR indicate the Li⁺ ions coordinate with the soft and hard segments. Additionally, the crystallinity of the PEG soft segment and the ordered hydrogen-bonded urea carbonyl groups decreased with increasing salt concentration. Impedance spectroscopy (IS) measurements show that the PUU electrolyte with the high phase separation degree has the high ionic conductivity. The hard-segment T_g and the soft-segment T_m influence the conductivity behavior of polyelectrolytes with increasing measurement temperature.     

Effect of the drafting force on the strength of the bottom of the spinneret

In spinning basalt fibres, the drafting force is in the same range as in spinning of glass fibres. The effect of the drafting force can not be considered in the calculation for the strength and rigidity of the bottom of the spinneret. __________ Translated from Khimicheskie Volokna, No. 5, pp. 47–50, September–October, 2007.