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磷钼酸喹啉重量法测定磷矿石和磷精矿中五氧化二磷含量,方法准确可靠,是磷矿的仲裁分析法。本文探讨了用普通滤纸代替玻璃坩埚式滤器分析五氧化二磷含量的可行性。试验表明,用普通滤纸代替玻璃坩埚式滤器切实可行,方法精密度和准确度能满足常规分析要求。 相似文献
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在聚合物注入液、采出液的含聚浓度检测标准中提到配制母液的浓度为1000mg/L(《Q/SY DQ0925-2012》、《Q/SY DQ0928-2011》),在实际检测过程中,配制站的母液浓度并不是1000mg/L,为此,我们在制作标准曲线时,采用中分、高分的干粉和清水、污水分别配制了1000mg/L和5000mg/L的母液做比对。在检测采出样的过程中,标准中未提到用何种滤纸过滤样品,我们也对定性、定量两种滤纸进行比较。对重质纯碱的质量检验,现用的检测标准(《GB/T 210.2-2004》)中,对氯化物含量的检测,我们提出用硝酸银滴定的方法,通过大量做样对数值进行比对。 相似文献
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模拟分析滤纸过滤阻力与各影响因素的关系。根据模拟需要,对不同种常见机油滤纸进行了孔隙率、厚度、过滤阻力、含尘浓度和过滤速度等测试;并依据实验数据,分析得到了滤纸模拟模型,模拟边界条件。通过模拟得到了各影响因素变化时,滤纸过滤阻力随之变化的趋势,给出了滤纸过滤性能的模拟与实验对比结果,验证了模拟方法的可靠性,最后回归分析得到滤纸压降与含尘浓度、过滤速度及孔隙率的关系,为滤纸的优化选择及设计提供参考依据。 相似文献
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滤纸烘重法测定镀铬液中硫酸含量 总被引:2,自引:2,他引:0
镀铬工艺对硫酸含量的控制十分重要。我们避繁就简,采用了滤纸烘重法,叙述如下。1实验方法1.1滤纸的准备滤纸烘重法,必须充分地考虑到滤纸重量的变化。滤纸有很强的吸湿性,尤其是在空气相对湿度较大时,一张经过干燥的滤纸与吸收了空气中水份的滤纸重量,相差达十... 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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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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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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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