Influences on the Needle Penetration of Petroleum Wax

This paper deals with the dependence of needle penetration of petroleum waxes on structure and content of the crystalline fraction as well as the viscosity of the amorphous fraction. The crystallinity is defined as the relation of the total crystallization enthalpy of the respective wax to the ideal crystallization enthalpy of the n-alkane that is equivalent to the average C atom number of the wax. The viscosity of the amorphous phase is defined by the viscosity of the molten wax at 100°C. It is shown that both parameters have a decisive influence on the needle penetration-temperature behavior of waxes. The complete cross-linking of the crystal lattice is of great significance for the properties. Influences of wax composition on crystallinity and viscosity are discussed.     

石蜡加氢装置成品机械杂质成因及对策

从石蜡生产的工艺流程、装置运行周期、中间罐区管理、原料质量等几个方面对石蜡成品中的机械杂质成因进行了分析，并提出了相应的对策。     

Studies on Carbon Number Distribution of High Melting Microcrystalline Waxes

Carbon number distribution of microcrystalline wax derived from tank sludges of Bombay High crude oil (India) and its various high melting fractions have been studied by High Temperature Gas Chromatography (HTGC). Binodal, Gaussian distribution and a wide range of alkanes, ranging from C₂₁-C₇₅, along with their many isomers with predominant alkanes being C₄₀ and C₆₇, have been observed in the microcrystalline wax. Higher melting wax fractions have Gaussian distribution.     

浅析不同时期雕漆工艺特色

雕漆工艺作为漆器工艺中的特种工艺,历史悠久,艺术魅力独特,为很多藏家所喜爱。了解不同历史时期的雕漆器所呈现出来的艺术特色,不仅有利于雕漆作品在收藏市场的价值定位,同时更是推进传统雕漆器走进更为广阔的空间领域的有效手段。基于此点,特撰本文。     

大漆媒材与传统室内装饰

本文探讨了大漆媒材在传统室内空间装饰中的应用,其应用主要基于能防腐、有黏连性、能成膜且具光泽、能保护木构件等特性。从大漆涂饰、丹漆施彩、雕梁画栋与家具装饰四个方面阐述了大漆媒材的色彩表现。     

锅炉车蒸汽热洗工艺在侏罗系油井中的应用

目前常用的热力清蜡主要采用常规热洗和自能热洗两种,侏罗系、常用的自能热洗由于受到燃气限制、常规热洗和投加清蜡剂成本高、效果不理想,因此需要寻找一种适合侏罗系油井的高效清防蜡技术。锅炉车热洗清蜡与投加清蜡剂方式相比,清蜡效果较好,避免了员工现场的井口加药繁琐的操作,降低了员工劳动强度,更加适应于目前长庆油田无人值守的数字化运行管理模式。     

DSC法测量蜡的熔点及相变焓

蜡的熔点是表征蜡物化性质的重要指标之一,虽然是常见的物理性质,但要获得科学而准确的测试结果并非易事。文中通过采用差示扫描量热(DSC)法分别对58号石蜡和费托蜡的熔点及相变焓进行测定,研究了蜡的液固相转变过程。取熔融石蜡的DSC固化曲线放热峰的两端基线与前沿斜率最大点切线的交点为熔化点,即熔点。结果表明:与GB/T2539—2008法相比较,DSC法更加简便,试样用量少,有良好的精确度和重复性等特点。     

Contrast Agent Incorporation into Silicone Enables Real‐Time Flow‐Structure Analysis of Mammalian Vein‐Inspired Soft Pumps

The construction of machines consisting essentially of soft parts is a nascent and multidisciplinary research field between material science, machine engineering, and robotics. Soft silicones represent a promising class of materials for the creation of a vast multitude of biologically inspired entities. In the present work, a new type of mammalian vein‐inspired soft silicone pump is introduced and characterized, which is fabricated by virtual lost‐wax casting of 3D‐printed injection molds. These pumps can be actuated pneumatically or by internal gas combustion and preserve their functionality even after a freezing/unfreezing cycle. The possibility of using medical examination methods such as ultrasonic imaging to directly access flow information inside soft pumps is shown. Based on soda lime glass microspheres, a method is demonstrated to enhance contrast properties during such color online Doppler imaging for a detailed understanding of the inner fluid‐structure interactions.     

Adhesion of Wax Droplets to Porous Polymer Surfaces

An experimental study was done to measure the force of adhesion of molten wax droplets, 3.1 mm in diameter, dropped from heights ranging from 20 to 50 mm onto porous polyethylene and Teflon surfaces. The Teflon surface had 0.25-mm holes drilled in it and the three polyethylene surfaces had random pores with mean diameters of 35, 70, and 125 μm, respectively. The force required to remove the solidified ink from the surface was measured using a pull test. Wax splats were attached to the substrate by both adhesive and cohesive forces. The cohesive force was calculated by multiplying the ultimate tensile strength of the wax (2.2 MPa) by the cross-sectional area of the wax penetrating into surface pores. The adhesive force was obtained by multiplying the contact area between the wax and substrate by the adhesion strength per unit area, estimated to be 0.2 MPa for polyethylene and 0.1 MPa for Teflon surfaces. The contact area between splats and the substrate was typically about 60–70% of the splat area. The edges of splats lifted up, preventing complete contact.