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101.
以某未知成分的主流原油破乳剂A为对象进行有效成分检测技术的研究。通过柱层析和萃取法对破乳剂的组分进行分离,利用红外光谱、气相色谱和气相色谱与质谱联用等仪器进行结构分析,用酸性亚甲基蓝法、硫氰酸钴铵法和浊点法鉴别破乳剂所含表面活性剂类型,用硫氰酸钴铵光度法对聚醚进行了定量检测。结果表明,破乳剂A所用溶剂为二甲苯,有效成分为丙二醇聚氧丙烯聚氧乙烯聚醚,有效含量分别为10.5%(以破乳剂A样品计)和21.8%(以烘干后的破乳剂A计),并含有少量烷基苯磺酸钠(0.47%);聚醚中聚氧乙烯与聚氧丙烯链段的摩尔比约为1.13。在油田的实际应用中,可在定性分析的基础上选取硫氰酸钴铵光度法快速检测聚醚类破乳剂的有效成分浓度。  相似文献   
102.
以纳米Al_2O_3改性三聚氰胺-脲醛树脂(MUF)为壁材,环氧树脂为芯材,采用原位聚合法合成了微胶囊,并采用光学显微镜(OM)、扫描电子显微镜(SEM)、红外光谱仪(FTIR)、X射线光电子能谱分析仪(XPS)、热重分析仪(TGA)等对其表面形貌、结构及热性能等进行了表征和测试;将改性后的微胶囊加入自修复环氧树脂涂层中,并对其热性能、力学性能、自修复性能及电化学性能进行测试。结果表明,当芯壁比为1.5:1、纳米Al_2O_3质量分数为4.5%时,纳米Al_2O_3在壁材中均匀分布,微胶囊的表面粗糙度和热稳定性均增加。当涂层中改性微胶囊质量分数为5%时,涂层的热稳定性提高,且涂层的拉伸强度、弯曲强度、冲击强度及粘结强度分别提高了111.9%、55.1%、10.6%和51.9%;制备的涂层具备较好的自修复性能;涂层的耐腐蚀性能随着微胶囊质量分数的增大而增强。  相似文献   
103.
《Ceramics International》2020,46(8):11898-11904
Nanomaterials with ultraviolet/near-infrared (UV/NIR) shielding property have great potential for developing energy-saving windows. In this work, we report low-cost W18O49 nanorods as UV/NIR shielding material. W18O49 nanorods with the length of ~20 or ~60 nm were prepared by simple solvothermal method, and they exhibited strong size-dependent absorption in the UV/NIR region. By mixing W18O49 nanorods with polydimethylsiloxane (PDMS), W18O49@PDMS films were constructed and they could shield 55.58% of UV and 75.89% of NIR light while transmit 58.03% of visible light. A sealed box with W18O49@PDMS-coated glass as the window exhibited a minimal temperature elevation (△T = 9.2 °C) compared to those coated with pure glass (△T = 18.2 °C) or ITO glass (△T = 12.1 °C), under the irradiation of solar light (0.6 W cm−2). Additionally, the films had a contact angle of 122 ± 2°, showing self-cleaning ability. Therefore, W18O49@PDMS films can act as cost-efficient UV/NIR-shielding and self-cleaning film.  相似文献   
104.
致密低渗透储层多尺度裂缝及其形成地质条件   总被引:2,自引:0,他引:2  
根据限制致密低渗透砂岩储层天然裂缝扩展的岩石力学层及其界面特征,提出了多尺度裂缝的划分标准,探讨了多尺度裂缝形成的地质条件。根据油藏内天然裂缝规模及其控制界面,将天然裂缝分为大尺度裂缝、中尺度裂缝、小尺度裂缝和微尺度裂缝4级。大尺度裂缝在砂层组内发育,切割夹层,受隔层控制,延伸长度通常为百米级;中尺度裂缝在复合砂体内发育,切割层面,受夹层控制,延伸长度通常为数十米级;小尺度裂缝在单砂体内发育,受层面控制,延伸长度一般为米级至十米级;微尺度裂缝需要借助微观分析手段进行观察和识别,延伸长度一般为厘米级以下。不同尺度裂缝具有幂律分布的特点。裂缝尺度越大,数量越少;裂缝尺度越小,数量越多。多尺度裂缝的形成主要受岩石力学性质差异、岩石力学边界厚度和构造应力的控制。构造应力越大,越容易形成穿层的大尺度裂缝,较大的岩石力学性质差异和较厚的岩石力学边界才能够限制裂缝扩展;构造应力越小,越容易形成小尺度裂缝,较小的岩石力学性质差异和较薄的岩石力学边界就能够限制裂缝扩展。不同尺度裂缝对致密低渗透油藏的作用不同。微尺度裂缝主要起储集空间作用,改善了致密低渗透储层的储渗性能,是致密低渗透油藏稳产的重要因素;小尺度裂缝起储集空间和渗流通道作用,它们是控制致密低渗透储层早期产量高低的关键因素;大、中尺度裂缝主要起渗流作用,它们影响油藏开发中后期的剩余油分布规律。  相似文献   
105.
Bringing a single still image into reality is a challenging topic in computer animation because the driven and structural information in single still image is inadequate. In this paper, we present an image animating method for enhancing single still image in social media with virtual realistic and animated motions without prior information. We imitate the interaction between the active objects in an image and their neighboring passive objects. The existing actions in the image and the virtual specified force are employed to animate the active objects. Observing that the change between two subsequent motions of the active objects derives a motion tendency, we can calculate a virtual driving force based on the motion tendency. By virtue of the virtual driving force, the stochastic motion texture is used to animate the passive objects. Finally, the convolutional neural network is employed to optimize the virtual motion animations. In this way, the proposed method produces visually natural results while guaranteeing motion harmony between active objects and passive objects. To demonstrate the applicability and rationality of virtual animation driving force, our method generates several animations from still images in Social Media.  相似文献   
106.
The facial fit of respirators is crucial for determining how effectively respirators may protect users from exposure to airborne contaminants, when their use is required in the workplace. In the Chilean market, all the respirators available have been designed and manufactured using foreign regulations. The aim of this research was to determine the facial dimensions in a sample of Chilean workers (users or potential users of respiratory protective equipment) and the possible mismatch between their anthropometric characteristics and the respirator fit test panels proposed by Los Alamos National Laboratory (LANL) and National Institute for Occupational Safety and Health (NIOSH). An anthropometric survey that included 11 measurements was conducted, based on ISO/TS 16976–2 and ISO 15535 to ensure the highest standards possible, and a total of 474 workers (female: 229, male: 245), aged 18–66 years old participated in the survey. The anthropometric measurements were then contrasted with the fit test panels used in LANL (for half and full facepieces) and NIOSH (Bivariate and Principal component analysis (PCA)), to verify the level of mismatch. The results showed that LANL panels presented a level of mismatch of 11.8% and 21% for the half-facepiece and the full-facepiece, respectively. Considering the NIOSH bivariate and PCA panels, 4.6% and 4.4% of the sample remains without an assigned cell, respectively. It can be concluded that the LANL panels for half and full facepieces do not match the facial dimensions of the Chilean working population. The panels developed by NIOSH and considered by the ISO/TS 16976–2 (bivariate and PCA), are applicable to the Chilean working population.Relevance for the IndustryThis research provides anthropometric measurements of Chilean workers, to determine the dimensions for half- and full-facepiece respirators, which are currently not available. The NIOSH or ISO fit test panels, as opposed to LANL panels, should be used when manufacturing respirators for Chilean workers.  相似文献   
107.
分析影响致密砂岩渗透率的主控因素并准确预测致密砂岩渗透率对致密油气藏的开发具有重要意义。以鄂尔多斯盆地延长组致密砂岩为研究对象,基于高压压汞和核磁共振对致密砂岩渗透率主控因素进行了研究,分别评价并优选了更适用于致密砂岩的基于高压压汞和核磁共振的渗透率预测模型。结果表明:影响致密砂岩渗透率的主要因素是孔喉半径,其中中值孔喉半径与致密砂岩渗透率相关性最强;与核磁共振T2加权平均值相比,T2几何均值与致密砂岩渗透率的相关性更强;在3种不同的核磁共振渗透率预测模型中,SDR-REV模型的预测效果要优于SDR模型和KCT2w模型;在3种不同的高压压汞渗透率预测模型中,基于r40r45的Winland模型渗透率预测精度较高。研究成果对鄂尔多斯盆地延长组致密砂岩的进一步有效开发具有指导意义。  相似文献   
108.
Huang  Liang  Cao  Yan  Jia  Feng  Lei  Yan 《Microsystem Technologies》2020,26(3):947-955

With the widespread application of non-conducting tough materials, such as ultra-white glass in MEMS recent years, many difficulties have arisen in the processing of these kind of material with eigen-structure characteristics. By analyzing the generation principle of interelectrode gas film of this kind of material, the breakdown characteristics of gas film under different power supply parameters are studied, and the relationship between the process parameters and the forming quality, material removal rate under the condition of gas film stability is further analyzed, so as to realize the optimal selection and the ultra-white glass micro array holes successfully machined.

  相似文献   
109.
A novel (1-x)Na0.5Bi0.5TiO3-xBaHfO3 (abbreviated as (1-x)NBT-xBH) transparent ceramic was fabricated by the solid state reaction method. X-ray diffraction analysis showed that NBT-based transparent ceramics exhibit a cubic-like perovskite structure and the solid solubility of BH in NBT reached to 0.15. The Landau-Devonshire theory and I-E curves revealed that the transition between the antiferroelectric like phase and the ferroelectric phase deeply relies on the variation of composition and free energy. One sample (x = 0.15) was found to show a high dielectric constant (˜2418±10%) over the temperature range 57–400 °C. These ceramics also exhibited a high discharge energy density (Wd) of 2.1 J/cm3 and a high maximum polarization Pm of 34 μC/cm2 under relatively low electric fields which were less than 175 kV/cm. There was also high transparency in the visible spectra (more than 0.5) when the sample thickness was 250 μm.  相似文献   
110.
The corrosion behavior of pure Mg17Al12 and the effect of ball milling in presence of additives (i.e. graphite (G) and magnesium chloride (MgCl2)) are evaluated in 3.5 wt% NaCl aqueous solution using electrochemical polarization and impedance measurements. Pure Mg17Al12 and milled Mg17Al12 without additives and with MgCl2 present an open current potential (OCP) of −1.2 V/SCE while Mg17Al12 + G shows a slightly higher OCP (+10% maximum). Mg17Al12 corrodes with low kinetics and an increase of corrosion rate for the milled Mg17Al12 is observed. The corrosion current densities (Jcorr) derived from the Tafel plots, exhibit their corrosion reactivity as follow: Mg17Al12 < Mg17Al12 5h < Mg17Al12 + G 5h < Mg17Al12 + MgCl2 5h. Electrochemical impedance spectroscopy (EIS) results are in good agreement with the measured Jcorr. Randles circuit models are established for all samples to explain their surface behavior in the aqueous NaCl solution. The variation of the fitted parameters is attributed either to the effect of ball milling or to the effect of the additive. Our results are helpful in elucidating the effect of ball milling and the additives.  相似文献   
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