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研究物理防老剂(微晶蜡A)和化学防老剂(防老剂RD,3100和4020)对轮胎胎侧胶耐臭氧老化性能和耐天候老化性能的影响。结果表明:与未添加防护体系的硫化胶相比,添加化学防老剂或微晶蜡A的硫化胶耐臭氧老化性能提高,微晶蜡A的防护效果较好;添加微晶蜡A的硫化胶耐天候老化性能大幅提高;添加化学防老剂和微晶蜡A的硫化胶耐臭氧老化性能和耐天候老化性能最佳;成品轮胎行驶50 000 km后,胎侧弹性良好,胎面和胎侧均没有裂纹产生,轮胎使用正常。 相似文献
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众所周知,胎侧是轮胎侧向变形最大的部位,经受频繁的屈挠变形,故胶料应具有良好的耐屈挠性。此外,胎侧还直接与大气接触,要求有良好的耐天候老化性,因此,防老剂的使用至关重要。本文将在轮胎胎侧胶中用防老剂8PPD-35代替防老剂RD进行应用研究试验的情况报告如下:一、实验1.主要原材料3L标准胶越南产;防老剂RD天津某厂产;防老剂8PPD-35山东泰安飞达助剂有限公司产;其余原材料均为轮胎生产常用原材料。2.试验配方1号配方:天然胶30,合成胶70,活性剂7,炭黑70,芳烃油14,硫化剂2.8,防老剂RD1,其它13.6,合计208.4。2号配方:天然胶30,合成胶70… 相似文献
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<正>由江苏通用科技股份有限公司申请的专利(公开号CN 108976504A,公开日期2018-12-11)"低氧化锌含量的轮胎胎侧胶及其制备方法",涉及一种低氧化锌含量的轮胎胎侧胶及其制备方法,采用以下工艺步骤制备。(1)一段混炼:将天然橡胶、顺丁橡胶、炭黑N375、氧化锌、硬脂酸、增粘树脂、芳烃油、防老剂RD、防老剂4020和B型微晶蜡投入密炼机中进行混炼,转子转速为40~55r·min~(-1),压砣压力为4.0~5.5 MPa,排胶 相似文献
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Dinesh Singh J. K. Gehlawat Musti S. Rao 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1990,47(2):127-136
Oslefins and diolefins are important intermediates in the petrochemical industry and the future promises a further substantial increase in demand. While several catalysts have been formulated in the past for the abstraction of hydrogen from butenes and propylene, these catalysts are inefficient in the abstraction of first hydrogen from butane. Bismuth molybdates (β and γ-phases) containing iron oxide and supported on alumina are used as catalysts in the present investigation on the oxidative dehydrogenation of n-butane. Effects of catalyst content, temperature and oxygen: n-butane ratio on conversion and selectivity to butadiene and (C4H8 + C4H6) are studied in the following ranges of experimental conditions: β-bismuth molybdate/100 mol support I(K), 3–9; γ-bismuth molybdate/100 mol support I(K), 5-20; temperature, 400–500°C; O2: butane ratio, 0.6:1.7. 相似文献
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考登钢作为一种高耐候结构钢,广泛应用于各个领域。在火力发电方面,考登钢主要应用在工作环境比较恶劣的烟气加热器和空气预热器中。考登钢表面涂搪的目的就是进一步提高其耐腐蚀性能,延长使用寿命。为了提高考登钢元件的使用寿命,对考登钢表面涂搪瓷的可行性、密着性能、瓷釉、工艺控制、质量保证等方面进行了研究。 相似文献
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A viscometer used to measure the viscosity of 10 μl of a liquid, must be miniaturized down, and the liquid velocity gradient in the channel used to determine the viscosity coefficient. Two major factors that affect the liquid velocity are the mechanical forces exerted by the mechanical motors and electromagnetic forces. In this study, electrowetting on dielectric (EWOD) is adopted to drive liquids. Variously sized electrodes on a chip, and two shapes of channel are employed to measure the velocity gradient to determine the viscosity coefficient. The device is fabricated by microelectromechanical system (MEMS) technology. The dielectric layer used in EWOD has a high dielectric constant, BST (Ba0.7Sr0.3TiO3), to reduce the required applied voltage; its surface is coated with hydrophobic polymer, polytetrafluoro-ethylene (PTFE, Teflon® AF DuPont). Experimental results demonstrate that liquids can be pulled at 660 μm/s in linear channels by applying a voltage of 15 V. 相似文献
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研究了温度和pH值对漆酶酶活以及漆酶处理纤维压制纤维板性能的影响。结果表明,pH较低、温度较高时漆酶酶活较高,压制的纤维板强度性能较好。但温度太高(60~80℃),延长加热时间,漆酶稳定性变差,酶活明显降低,压制纤维板的强度下降。 相似文献
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In reexamining medium effects on photochemical reactions, we have emphasized those on unequilibrated excited species such as the Franck-Condon species. Despite recent advances in femtochemistry, such a discussion in molecular photochemistry is uncommon, and the problem remains challenging on account of the extremely short-lived excited species. However, in such cases, a small perturbation resulting from, for example, weak guest-host interactions could turn into a determining factor in dictating the course of a photochemical channel of deactivation. Examples of medium-directed diabatic processes have been examined with this idea in mind. A modified view on rhodopsin photoisomerization is presented along with the consideration that confinement does not necessarily lead to inhibition of reactions of the trapped substrate. 相似文献
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采用实验方法考察工艺参数对沉降斑的影响。基于一个带凸台的平板模具,采用L27(313)正交矩阵进行实验,研究了几何尺寸、熔体温度、注射时间、保压压力及保压时间对厚度突变处沉降斑形成的影响,同时还考虑了熔体温度和注射时间以及保压压力和注射时间之间的交互作用影响;通过性噪比分析和F检验优化成型工艺条件并对工艺参数的影响进行显著性分析。结果表明,对于厚度突变的平板制品,厚度突变的程度对其沉降斑形成的影响最大,其次为熔体温度,保压压力,保压时间等;采取减小厚度变化,降低熔体温度或增加保压压力和保压时间等措施,可以减小厚度突变处沉降斑,从而减少其对外观质量的影响;因素之间的交互作用对制品沉降斑的形成有一定的影响,熔体温度B和注射时间C之间的交互作用影响较为明显,而保压压力D和注射时间C之间的交互作用对该质量指标的影响最小,可以并入误差。 相似文献