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41.
42.
研究3+8×0.33ST钢丝帘线在全钢载重子午线轮胎带束层中的应用。结果表明:与3+8×0.33HT钢丝帘线相比,3+8×0.33ST钢丝帘线单位直径强度和刚度大,压延厚度小,以其替代3+8×0.33HT钢丝帘线用于全钢载重子午线轮胎带束层,可以提高成品轮胎的强度和耐久性能,同时可降低生产成本。 相似文献
43.
对于含黏土矿物较高的页岩油储层,地层水的矿化度可高达4.786×103 mol·m?3,压裂过程中与注入的低矿化度压裂液形成的渗透压作用显著。为探究渗透压对渗吸的影响作用,建立了综合考虑渗透压和毛管力渗吸作用的油水两相二维离散裂缝网络模型,开展了页岩油储层压裂液泵注和关井阶段渗透压、毛管力、关井时间、盐浓度、膜效率、分支缝面积占比等对渗吸的影响规律研究。结果表明:①滤失主要由压力差、毛管力和渗透压3种机制驱动,其中压力差是滤失的关键控制机制;②关井时间对压裂液的渗吸作用影响较大,关井50 d时,前15 d渗吸量可达到总渗吸量的80%,且关井压力扩散会波及到两侧压裂段;③与压力扩散相比,渗透压达到平衡的时间较长,对于地层水矿化度为4.786×103 mol·m?3的情况,裂缝附近的矿化度达到600 mol·m?3左右所需关井时间为50 d;④由于压力差是渗吸主要驱动力,页岩膜效率对渗透压力扩散影响微弱,页岩膜效率30%与5%相比渗吸量仅增加4%;⑤对于密切割压裂,关井后,含水饱和度受小间距水力裂缝控制,分支缝对渗吸含水饱和度的影响有限。 相似文献
44.
预焙铝电解槽阳极钢爪自焙保护环优化技术 总被引:1,自引:0,他引:1
就目前预焙铝电解槽所用的自焙保护环的制作进行了研究.提出了优化方案,通过工业试验认为.自焙保护环的制作技术优化后.可以给企业创造显著的经济效益。 相似文献
45.
46.
Pd catalysts supported on TiO2, ZrO2, ZSM-5, MCM-41 and activated carbon were used in catalytic wet oxidation of hydrocarbons such as phenol, m-cresol and m-xylene.
It was found that the Pd/TiO2 catalyst was highly effective in the wet oxidation of hydrocarbon. The activities of catalysts with various hydrocarbon species,
catalyst support, oxidation state of catalyst performed in a 3-phase slurry reactor show that reaction on Pd surface is more
favorable than that in aqueous phase and that the active site is oxidized Pd in catalytic wet air oxidation of hydrocarbons.
Based on the experimental results, a plausible reaction mechanism of wet oxidation of hydrocarbons catalyzed over Pd/TiO2 catalyst was proposed. This catalyst is superior to other oxide catalysts because it suppressed the formation of hardly-degradable
organic intermediates and polymer. 相似文献
47.
Kazuyuki Tsubone Noriko Uchida Kunio Mimura 《Journal of the American Oil Chemists' Society》1990,67(7):451-454
A series of new amphoteric surfactants having a phosphoric acid group, a tertiary amino group and a 2-hydroxyalkyl group, sodium 2-(N-2-hydroxyalkyl-N-methyl-amino)ethyl hydrogen phosphates (alkyl: n-tetradecyl, n-hexadecyl, n-octadecyl), were prepared by an addition reaction of 1,2-epoxyalkanes to N-methylaminoethanol, followed by the introduction of a phosphoric acid group and neutralization with sodium hydroxide. The structures of these compounds were confirmed by spectroscopy and elemental analysis. The solubility in solvents, Krafft point, surface tension, critical micelle concentration (CMC), occupation area of the molecule at the surface of aqueous solutions and foaming power were measured. It was shown that a 2-hydroxyethyl group in a long alkyl chain seemed to behave as a hydrophobic part. 相似文献
48.
冷却塔的冷却效果主要由淋水填料的冷却数和冷却塔的有效高度决定,淋水填料的换热性能决定了冷却塔的主要换热效果。为提高抗震冷却塔的抗震效果,淋水填料采用金属填料。通过在某工程中抗震冷却塔金属填料与普通塑料填料应用的对比分析,研究金属填料的特点及适用性,为抗震冷却塔的设计提供依据。 相似文献
49.
This work investigates the electric field effect on nitrogen oxide (NO) pollutant formation and emission composition of premixed flames in order to provide better insight on the mechanism of controlling the combustion process by electro-physical means. The present study aims to investigate experimentally the effect of radial DC electric field on premixed laminar methane flame. The electric field effect on flame shape, emission composition and NO emission index of flame is investigated experimentally under the action of direct-current electric field under varying equivalence ratio and level of oxygen enrichment. The results show that ionic wind effects cause the distortion in flame shape. The ionic wind effects diminish with increasing flow rate and level of oxygen enrichment. Minimal effects on NO are measured for flames under the influence of electric field and vanished as the level of oxygen enrichment is increased. This was well supported by the temperature profile measurement in the post flame gas showing no field-induced modification also. It seemed that the action of an electric field on a flame with a geometry that remains practically undeformed produces very minimal effect on pollutant emission. 相似文献
50.
《Diamond and Related Materials》2005,14(10):1669-1672
Disparities prevail among the reported hardness and fracture toughness values for hard and brittle materials. A better understanding of the physical nature of hardness and fracture toughness and a standardized technique for reliable measurements of these quantities is urgently needed. We strongly recommend the use of the measured hardness after the bend in the hardness versus load (H−FLoad) curve, when the hardness approaches its asymptotic value. The present work reports a systematic study of hardness and fracture toughness on moissanite (single crystal hexagonal silicon carbide, 6H-SiC) samples. The measurements were performed over a broad load range from 0.49 to 294 N with the direct indentation method. Asymptotic values of Knoop hardness of HK = 19 GPa and Vickers hardness of HV = 22 GPa were reached at a high load between 50 N and 100 N. A consistent fracture toughness of KIC = 1.8 MPa·m1/2 was obtained across the entire load range. Our study presents experimental results for the hardness and fracture toughness of moissanite in the asymptotic-hardness region, and it raises concern regarding the application of moissanite single crystals as anvil material under shear/fracture conditions. 相似文献