应用TEMA-9th进行膨胀节分析设计

按照TEMA-9th,使用有限元分析软件ANSYS对膨胀节模型进行分析设计。简单叙述了TEMA-9th关于膨胀节计算的要求及关键步骤,并通过实例较为完整地对膨胀节进行了分析,对膨胀节在使用有限元分析设计中起到了指导作用。对ANSYS软件分析结果与TEMA-8th标准计算结果相比较,TEMA-8th设计值远大于有限元分析值,此标准在膨胀节的设计中仍具有较大的保守性。     

承压反应釜的屈曲分析和临界载荷预测

采用有限元分析手段,对一典型的反应釜结构进行力学分析,并根据模态分析结果对其稳定性进行校核。该方法可为薄壁壳体类承压设备的失稳分析提供参考。     

四川珙县原料性能的研究

对珙县原料进行了全面地分析,首先对其外观、干燥性能、化学成分进行分析,其次对烧成性能进行分析,并经分析讨论后得出结论。     

ICP分析法测定煤灰中铝含量

通过利用ICP等离子耦合光谱仪对元素测定的特性,对煤灰中铝含量进行定量分析,该分析方法定量准确,分析操作简单,分析效率高,可以大批量分析,对生产的指导作用强.     

4000 m~3液化石油气球罐分析设计讨论

通过压力容器分析设计的方法,使用数值分析的方式,对球形储罐的应力分析进行了论述,对其结构、载荷等问题进行了说明,为球罐分析设计提供了可供工程参照的方法。并对4 000 m~3,振动按双质点考虑的大型球罐的地震工况进行了讨论,对球罐这种剪切型振动只考虑水平地震。通过ANSYS有限元软件建模分析,得出各种工况下球罐的应力和变形。     

高原地区气体分析中压差对分析结果的影响

高原地区大气压低于标准大气压,对纯碱厂分析一些气体含量有一定的影响。通过试验,计算分析压差对相关气体分析结果的影响。     

吉林某煤矸石作丁苯橡胶补强填料的研究

通过化学成分分析、粒度分析、X-射线衍射、SEM分析等方法,对吉林某矿区的煤矸石的性质进行了研究,并对煤矸石进行化学改性,利用改性后的煤矸石部分代替炭黑作橡胶补强材料,制品的拔出力均高于国标和企业标准,并对其进行了补强机理分析.     

酸碱滴定终点误差分析

为了减少酸碱滴定利用指示剂变色来确定滴定终点的误差,提高分析测定结果的准确度.通过理论分析和实例分析,对酸碱滴定中不同的指示剂、不同浓度的被测物质进行了分析讨论,并根据溶液物料平衡和电荷平衡关系,直接推导得出酸碱滴定终点误差公式.对确定分析样品的取样量,选用适合浓度的试剂及适当的指示剂,减少滴定终点误差,提高分析结果的准确度具有指导意义.该方法易于理解和掌握,对酸碱滴定终点误差分析和计算具有指导意义.     

高一年级化学期末试卷分析

文章主要对盐城市时杨中学2009高一年级化学期末考试运用了区分度、难度、差异系数等方法进行了系统的科学化的定量分析。同时结合教学大纲对试卷的结构进行了分析,在结构分析后对试卷试题进行了定性分析。试卷分析可以检测试题能否真正达到考核目的,同时对试卷命越质量做出科学的鉴定和总结。在对试卷分析后可以对学生的学习状况有具体的了解,对教师的教学方法给予建议和改进。试卷分析结果有好有坏,文章站在客观公正的角度对高一期末的化学试卷进行了系统的分析,以便对教师的教学和学生的学习提供较好的参考和帮助。     

变频调速技术在矿井井下运输中的应用

矿井工程技术操作分析中,依据变频调速技术的操作分析标准,对变频调速的基本原理进行分析,准确的分析提成矿井井下有效运输的操作应用标准。矿井在运输过程中,需要根据具体的力量分析标准进行支撑分析,明确矿井工程的整体开展模式和借鉴参考范围。依据变频调速的操作,对矿井进行井下的运输分析,确定整体工程的实际情况,分析矿井运输的操作标准,确定符合变频调速的标准,对矿井下的运输作用进行分析,确定整体应用,提升综合矿井井下的作用标准效果。     

碘-聚乙烯醇在铜精矿测定铜含量中的应用

铜精矿中的存在组分较为复杂、干扰较多,因此在铜精矿铜量测定的过程中,选取合适的分析方法十分重要。碘量法方法成熟,操作简便,在铜精矿化学分析中的应用最为广泛。但由于采用标准法进行滴定时,其专属指示剂——淀粉指示剂与碘会形成大量吸附物,导致体系中的碘与硫代硫酸钠反应不充分且在偏酸性环境中,淀粉易被微生物分解变质,显色迟钝灵敏度下降。这些都将影响滴定终点的判断而造成分析误差。为了有效的避免此类情况的出现,引入聚乙烯醇表面活性剂,将改进型碘量法与标准法进行对比分析,发现新型指示剂消除了传统指示剂存在的干扰和弊端,提高了实验的准确度和精密度,PVA指示剂性能稳定且易于保存,在碘量分析中的表现更加出色。     

Reliability analysis of ceramic cutting tools in continuous and interrupted hard turning

Reliability analysis was carried out for ceramic cutting tools used in continuous and interrupted hard turning. On the basis of micromechanics and damage mechanics, statistical characteristics of the original defects in the tool material microstructure were evaluated and analyzed. A new tool performance indicator was proposed considering the combined effects of the original damage of the tool material microstructure, the macro-mechanical properties of the tool material and the external loads on the cutting tool. Statistical analysis of the tool performance indicator was performed for continuous and interrupted turning. The relationship between tool reliability and the probability distribution of tool performance indicator was identified. It was found that the original damage of the ceramic tool material followed a weibull distribution. The probability density of the original damage decreased as the original damage increased. When interrupted turning was adopted, tool performance indicator was relatively low and the indicator decreased as cutting length ratio became smaller. The indicator followed a weibull distribution and this was invariable when turning condition changed. Relatively low shape parameter and scale parameter in probability density function of tool performance indicator appeared when the tool was tested in interrupted turning and relatively small cutting length ratio was applied. Similar to tool performance indicator, tool lives obtained under different cutting conditions also followed a weibull distribution. When turning condition varied, shape parameter and scale parameter in probability density function of tool life changed in a similar way to those parameters in probability density function of tool performance indicator. Both the probability density function of tool life and that of tool performance indicator first increased and then decreased as the independent variable increased. Shape parameter for tool performance indicator can be used in the calculation of tool reliability when the cutting length ratio in interrupted turning was relatively small.     

Intermittent turning performance of ceramic tools with surface micro-geometry designed considering fluid-like behavior of chip

This work was performed to study the intermittent turning performance of ceramic tools with surface micro-geometry designed considering fluid-like behavior of chip. Quantitative analysis of the fluid-like behavior of chip was conducted for different cutting length ratios. Ceramic tools with different patterns of miro-textures on the rake face were designed on the basis of the fluid-like behavior of the chip and the skins of dung beetle and shark. An assessment indicator of tool performance was proposed covering external loads and tool microscopic mechanical property. The optimum pattern of miro-texture was distinguished based on the tool performance indicator. Tool lives obtained from turning tests and the values of indicator acquired at varying combinations of miro-texture pattern and cutting length ratio were compared to validate the assessment indicator of tool performance and the design method of tool surface micro-geometry. It was found that the similarity between chip and Newtonian fluid decreased as the chip flowed across tool rake face or the intermittence in turning process became higher. Assessment indicator of tool performance was put forward as the ratio of tool material fracture toughness to the maximum stress intensity factor on the cutting tool. Larger value of the indicator indicated better tool performance. Miro-texture pattern designed with the fluid-like behaviors of different chip zones considered was most efficient in enhancing the tool performance indicator. Experimental results of tool lives demonstrated the correctness of the assessment indicator of tool performance and the effectiveness of the design method of tool surface micro-geometry.     

色谱法分析石油中芳烃的研究进展

准确分析出石油中芳烃的种类和含量,是石油评价的一个重要指标。本文综述了色谱分析方法包括GC,GC×GC,HPLC,GC-MS等在石油中芳烃测定的应用进展。     

三价铬对测定退铬溶液中氢氧化钠的影响

在氢氧化钠溶液中用电解法退铬,退镀液中产生亚铬酸钠。用酸碱滴定法以酚酞作指示剂测定氢氧化钠,亚铬酸钠影响测定结果。在生产过程中发现,用传统的酸碱滴定法测定氢氧化钠误差很大。通过实验改进了氢氧化钠的测定方法,用氯化钡沉淀亚铬酸钠等,以酚酞作指示剂,用盐酸滴定氢氧化钠的质量浓度。     

炉渣酸度对制磷工艺及经济技术指标的影响分析

制磷电炉酸度值是衡量炉内化学还原反应完全与否的尺度，它是热法黄磷生产工艺操作控制的重要经济技术指标。针对其运行控制、影响因素及实际生产操作的消耗指标进行了比较、分析、优化，以期让生产和管理者高度重视。若生产中忽视对酸度值的正确认识和操作参数的优化，同样会导致成本上升。经济效益下降。     

Excel在酸碱中和滴定中应用

借助Excel表格数据处理方法,编写简单的应用程序,有利于学生了解反应中pH的变化、分析突跃变化的原因和指示剂的选择。通过对酸碱中和滴定曲线的绘制,还可以帮学生区分两个概念：中和终点和滴定终点,中和终点时酸碱恰好完全反应,而滴定终点是实验终止时的计量点。     

锅炉用水中微量硬度的测定方法研究

锅炉用水硬度是保障锅炉安全运行的一项重要指标.采用微量硬度指示剂法进行锅炉用水硬度分析,可以提高分析的精密度和准确度,延长试剂保存时间,适合锅炉水现场的快速分析.     

纺丝油剂用磷酸酯类单体分析方法

介绍了用于纺丝油剂用磷酸酯类单体的混合指示剂法、电位滴定法、核磁共振法、色谱法等分析方法,表述了各方法的优缺点,指出结合多种分析方法对该类单体进行分析是今后实现其结构和组成定量分析的方向。