稠油W/O乳状液增黏原因的灰熵关联研究

采用灰熵关联分析法研究了胜利稠油W/O乳状液增黏倍数与稠油组成(极性四组分含量、有机杂原子含量和过渡金属含量)和油品性质(稠油极性组分的分子质量和偶极矩)的关联。结果表明,在稠油组成中,沥青质和胶质的含量、O含量及Ni含量是影响W/O乳状液增黏倍数的重要因素;在稠油性质中,沥青质的性质是影响W/O乳状液的增黏倍数的关键因素。     

Room-temperature densification of MgO bulk ceramics with dispersed nitride phosphor particles

Wave conversion materials with high thermal conductivity are necessary for high-power semiconductor lighting. Ceramics have higher thermal conductivity than existing matrices such as resin or glass in which phosphor particles are dispersed. However, the high densification of ceramics generally requires high-temperature sintering, which degrades and alters the phosphor particles. In this study, we aimed to achieve the high densification of MgO ceramics at room temperature. Applying high hydrostatic pressure with water addition improved the sample packing ratio and promoted the formation of Mg(OH)₂. As a result, the relative density was ≥95%. Additionally, various nitride phosphor particles (CaAlSiN₃:Eu²⁺, β-SiAlON:Eu²⁺, and α-SiAlON:Eu²⁺) were dispersed in the MgO matrix at room temperature without degrading the luminescence property. The thermal conductivity of the obtained sample was about 8 W m^?1K^?1, 40 times higher than that of the epoxy matrix.     

H9P2W15V3/C催化1,4-丁二醇环化脱水制备四氢呋喃

以活性炭为载体,通过浸渍法制备了H9P2W15V3/C催化剂,对催化剂进行FT-IR表征。以催化1,4-丁二醇脱水制备四氢呋喃为探针反应,考察催化剂的酸催化性能。通过正交实验得出了最佳条件反应：w（催化剂）=3.93%（相对1,4丁二醇质量）,反应温度为185～190 ℃,反应时间为40 min,四氢呋喃平均收率达93.30%,催化剂重复使用3次,产率仍可达90.94%。本工艺具有绿色、安全、操作简单、收率高等优点。     

Influence of Coagulant Salt Addition on the Treatment of Oil‐in‐Water Emulsions by Centrifugation,Ultrafiltration, and Vacuum Evaporation

Abstract

Droplet size is a key factor in the treatment of oil‐in‐water (O/W) emulsions, because of its influence on emulsion properties. The addition of a coagulant salt generally causes emulsion destabilization, increasing the droplet size, and enhancing coalescence between oil droplets, which helps its further treatment. The influence of CaCl₂ addition on droplet size distribution of a commercial O/W emulsion used in machining processes was studied in order to facilitate oil removal and to improve its further treatment by centrifugation, ultrafiltration (UF) and vacuum evaporation. The critical coagulation concentration (CCC) was observed at a CaCl₂ concentration of 0.05 M. The quality of the final aqueous effluent, expressed as its chemical oxygen demand (COD) value, was compared for all treatments. The highest COD values were obtained for centrifugation, while the COD of the UF permeate was approximately constant for all UF trials. The best effluent quality was obtained by vacuum evaporation. A combination of these techniques should be appropriate for most industrial treatments of O/W emulsions, depending on the subsequent use of the resulting aqueous effluent.     

一种可靠的百兆以太网接口设计与实现

针对飞行器遥测系统研制的需要,设计并实现了一种基于FPGA和W5300的可靠的百兆以太网接口。本接口包括变压器隔离模块、以太网控制器和中央控制器3部分。接口采用UDP传输协议,实现了以6.5MB/s的速度可靠、稳定地接收遥测设备的数据流的功能。设计针对UDP协议本身存在的不可靠性,在接口硬件电路设计和软件逻辑设计上分别做了可靠性优化,基本上保证了传输链路的可靠性,确保了数据的完整性。     

Interfacial Crystallization of Diacylglycerols Rich in Medium‐ and Long‐Chain Fatty Acids in Water‐in‐Oil Emulsions

The effects of diacylglycerols rich in medium‐ and long‐chain fatty acids (MLCD) on the crystallization of hydrogenated palm oil (HPO) and formation of 10% water‐in‐oil (W/O) emulsion are studied, and compared with the common surfactants monostearoylglycerol (MSG) and polyglycerol polyricinoleate (PGPR). Polarized light microscopy reveals that emulsions made with MLCD form crystals around dispersed water droplets and promotes HPO crystallization at the oil‐water interface. Similar behavior is also observed in MSG‐stabilized emulsions, but is absent from emulsions made with PGPR. The large deformation yield value of the test W/O emulsion is increased four‐fold versus those stabilized via PGPR due to interfacial crystallization of HPO. However, there are no large differences in droplet size, solid fat content (SFC), thermal behavior or polymorphism to account for these substantial changes, implying that the spatial distribution of the HPO crystals within the crystal network is the driving factor responsible for the observed textural differences. MLCD‐covered water droplets act as active fillers and interact with surrounding fat crystals to enhance the rigidity of emulsion. This study provides new insights regarding the use of MLCD in W/O emulsions as template for interfacial crystallization and the possibility of tailoring their large deformation behavior. Practical Applications: MLCD is applied in preparing W/O emulsion. It is found that MLCD forms unique interfacial Pickering crystals around water droplets, which promote the surface‐inactive HPO nucleation at the oil‐water interface. Thus MLCD‐covered water droplets act as active fillers and interact with surrounding fat crystals, which can greatly enhance the rigidity of emulsion. This observation would provide a theoretical reference and practical basis for the application of the MLCD with appreciable nutritional properties in lipid‐rich products such as whipped cream, shortenings margarine, butter and ice cream, so as to substitute hydrogenated oil. MLCD‐stabilized emulsions can also be explored for the development of novel confectionery products, lipsticks, or controlled release matrices.     

Orthogonal ligation to spherical polymeric microparticles: Modular approaches for surface tailoring

Modular ligation strategies for the functionalization of polymeric microspheres provide new perspectives for their applications in material science. In the current trend article we highlight variable synthetic procedures for generating functional microspheres via orthogonal modular conjugation chemistries. An overview of the different surface chemistries available is provided, followed by surface-sensitive characterization techniques relevant for the microparticles. Finally, we explore future trends in modular orthogonal modification approaches on microparticles and provide an outlook on the perspectives that the field of surface-modification of polymeric microparticles holds.     

日产NHR-90W型催化剂失活原因分析

对日产NHR -90W催化剂在抚顺石化分公司石油二厂 6万t/a石蜡加氢装置运行情况进行了研究 ,证明该催化剂活性较高 ,对原料的适应性也较强。同时 ,对造成催化剂短期内失活的原因进行了分析 ,认为原料中铁离子含量过高是造成催化剂失活的主要原因。对相关装置生产控制提出了建议     

LUBRICATING OIL SLUDGE AND ITS DEMULSIFICATION

The oil sludge generated from the pretreatment of the used lubricating oil re-refinery is characterized as a complex and tight water/oil emulsion. The water content varies from 38 to 77 wt%. When the water content is low, the emulsion is of water in oil type. When the water content is high, small oil droplets exist in the dispersed water phase. The oil in the sludge is not different from the oil in the raw feed based on physical and thermal analyses. Centrifuging or gravitational settlement at elevated temperature does not show significant effects on water separation. The usage of inorganic chemicals and the typical demulsification agents from oil fields does not give satisfactory results either. The ultrasonic wave shows some dehydration on some samples. The freeze and thaw method proves to be the best method with over 90% of water removed from the oil sludge at the energy cost of about 0.01 US$/liter.     

Design of a super-hydrophilic/super-oleophobic g-C3N4/Ti(OH)4/PFOA nanocomposite coated mesh as a smart nanofilter with robust anti-fouling properties for separation of oil and water emulsions

The design and development of efficient approaches for water–oil separation have had widespread interest. This study aimed to synthesize nanocomposites based on Ti(OH)₄ and g-C₃N₄ nanosheets (CN-NS) to show experimentally that the inclusion of Ti(OH)₄ nanoparticles of 9.2 nm size into CN-NS leads to an improved oil-water separation efficiency and anti-fouling performance. So, a novel, reusable, and recyclable super-hydrophilic/underwater super-oleophobic CN-NS/Ti(OH)₄ nanocomposite-coated stainless steel mesh was developed to separate oil-in-water emulsions. Super-wettability was obtained in the CN-NS/Ti(OH)₄ nanocomposite with WCA = 0° and UOCA = 154°, respectively, showing significant super-hydrophilicity and underwater super-oleophobicity. Surface hydrophilicity increased after anchoring Ti(OH)₄ on the CN-NS surface, resulting from oxygen-containing functional groups and consequently making defects on the mesh surface. Enhanced underwater oleophobicity of nanocomposite coated mesh is attributed to its higher surface roughness, which is a result of its micro-nano meter and mesoporous hierarchical structure. Moreover, the self-cleaning property of the as-prepared mesh was demonstrated by visible light irradiation on the contaminated mesh. In addition, perfluorooctanoic acid (PFOA) reduced energy in CN-NS/Ti(OH)₄/PFOA mesh, resulting in a super-hydrophilic/super-oleophobic mesh. The CN-NS/Ti(OH)₄/PFOA nanocomposite-coated filter was observed to separate water from a 1 wt% water-in-oil emulsion at 0.2 bar pressure with a filtration flux of 317.2 L m⁻² h⁻¹ and 95% separation efficiency.