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1.
基于铼抑制Na2S2O8氧化萘酚绿B的褪色反应,结合紫外-可见分光光度法,建立了测定铼的新方法。确定了抑制体系的动力学条件,并计算了抑制反应的表观活化能Ea=84.65KJ/mol,反应速率常数K=1.95×10-4/s。在最佳实验条件下,铼的浓度在0.2~16.00mg/L范围内与相对吸光度呈良好的线性关系,检出限为6.0μg/L。用于钼矿焙烧烟尘中铼含量的测定,相对标准偏差为2.1%~2.9%,标准加入回收率为95.0%~104%,结果令人满意。  相似文献   

2.
本文采用Smartchem200全自动化学分析仪测定珠江八大口门水中的氨氮。在实验最佳条件下,氨氮浓度在0.01~2.00mg/L范围内与吸光度线性关系良好,线性回归方程为△A630=0.1814C-0.0003,相关系数为1.0000,检出限为0.007mg/L,样品加标回收率为94.3%~95.9%。该仪器测定珠江八大口门水中氨氮的结果令人满意。  相似文献   

3.
在硫酸介质中,二苯碳酰二肼可与铬(VI)发生显色反应生成紫红色的络合物,该络合物在540 nm波长处有最大吸收峰,由此建立测定磁性材料中铬(VI)含量的分光光度分析方法。本文对测定波长、显色pH值、显色剂用量以及显色时间等实验条件进行优化,在最佳实验条件下,络合物在540nm处的吸光度值与铬(VI)的浓度在0~0.3mg/L范围内呈良好的线性关系,其线性方程为A=0.839C-0.0048(c∶mg/L),相关系数r=0.9999;检出限为3.85×10~(-4)mg/L,回收率为94%~105%。采用碱浸煮方法提取磁性材料中的铬(VI),并用该方法对样品中铬(VI)的含量进行测定,并与SGS测得的结果进行对比。结果表明,该法的测定结果与SGS测得的结果相一致。该方法具有操作简便、快捷的优点,用于磁性材料中铬(VI)的测定,所得结果令人满意。  相似文献   

4.
使用萃取光度法对钼精矿浸出液中的铼进行测定,对萃取、显色及测定过程进行了试验,优化了掩蔽剂用量、萃取次数、萃取时间、pH、水浴温度及还原剂用量等条件。结果表明:在波长426nm处,铼在2~30μg/mL浓度范围内与其吸光度呈良好的线性关系,RSD小于2.3%,检出限(3s/k)为0.08μg/mL,回收率在91.2%~103.4.8%之间,与ICP-AES标准加入法进行对比,结果一致。  相似文献   

5.
痕量高碘酸银(Ⅲ)盐的分光光度法测定   总被引:1,自引:0,他引:1  
建立一种高碘酸银盐含量的分光光度测定方法。最大吸收波长为360nm,表观摩尔吸光系数ε=1.58 × 10~4L/(mol · cm),Ag( Ⅲ)含量在0.2~10 mg/L范围内,含量与吸光度符合比尔定律,与原子吸收分光光度法相比,相对偏差?3%,具有简便、准确的特点。  相似文献   

6.
根据对现有医疗废水检测方式的不足,设计了一种通过氯离子选择电极和可编程控制器(PLC)相结合的方法,实现了医疗废水中氯离子在线监测。在最优条件下,体系的测量范围为0~25800mg/L,线性回归方程为y=0.0006x+4.0136,相关系数R2=0.9999。该方法测量精度的相对标准偏差(RSD)为2.87%(100mg/L,n=6)和2.65%(20000mg/L,n=6)。加标回收率在99.8%~104.8%之间,平均回收率为101.8%(n=5),仪器的检出限(MDL)为2.925mg/L。  相似文献   

7.
高效液相色谱化学发光法测定阿魏酸哌嗪   总被引:1,自引:0,他引:1  
在碱性条件下,阿魏酸哌嗪对Luminol-NalO4发光体系有强烈的抑制作用。基于此建立了新的测定阿魏酸哌嗪的方法。本方法以C18反相键合相为色谱柱.用甲醇和水(35:65,V/V)为流动相,实现了对人体尿样中阿魏酸哌嗪的分离与测定。在最适宜条件下,方法的线性范围为1~20mg/L;检出限为0.3mg/L;相对标准偏差为1.4%(c=1.0mg/L,n=11)。  相似文献   

8.
用Smartchem140全自动化学分析仪测定了地表水中的氨氮。在最佳实验条件下,氨氮浓度在0.01~2.0mg/L范围内与吸光度线性关系良好,线性回归方程为△A630=0.45C+0.0014,相关系数为0.9999,检出限为0.005mg/L,加标回收率为98.7%~100.2%,方法简便实用,用于环境样品分析,所得结果令人满意。  相似文献   

9.
以盆栽丰香草莓为试材,研究了不同氮磷钾配比施肥对草莓植株生长和光合特性的影响。结果表明:适宜的氮(220.7 mg/L)、磷(110.35 mg/L)、钾(145 mg/L)能够促进草莓植株的生长发育。合理的氮磷钾配比对草莓光合速率影响极显著,氮的影响最大,磷最小。在该试验条件下氮磷钾最佳用量为N180 mg/L,P2O595.75 mg/L,K2O153.40 mg/L,最佳配比为N:P2O5:K2O=1:0.53:0.85。  相似文献   

10.
利用多接收器电感耦合等离子体质谱(MC-ICPMS)精确测定了天然岩石样品的铼含量。在膜除溶雾化进样条件下,铼测试样品中加入铱标准溶液,通过在线监控铱同位素的质量分馏行为来校正铼同位素的质量分馏。实验发现,铼和铱的质量分馏系数(fRe和 fIr)是不相等的,如果认为 fRe=fIr,将会导致187Re/185Re同位素比值偏低,但是 fRe/fIr比值固定不变,这样可以通过已知的 fIr 计算出 fRe,从而得到准确的187Re/185Re同位素比值。本工作利用这种经验的质量分馏校正方法,精确的测定出天然铼标准样品的187Re/185Re同位素比值为1.674 3±0.000 1(2σ, n=25),该结果与国际纯粹与应用化学委员会(IUPAC)推荐值(1.674 0±0.001 1)以及与N-TIMS测定值(1.675 ±0.001 4)在误差范围内一致。而且,采用该经验的质量分馏校正方法测得的天然铼标准样品的187Re/185Re同位素比值与采用 fRe=fIr 校正结果相比,准确度和外部重现性都明显提高。最后采用该方法准确测定出了天然岩石中Re含量,该结果与N-TIMS测定结果吻合。  相似文献   

11.
An engineering system may consist of several different types of components,belonging to such physical"domains"as mechanical,electrical,fluid,and thermal.It is t...  相似文献   

12.
The intersection of Quantum Technologies and Robotics Autonomy is explored in the present paper.The two areas are brought together in establishing an interdisci...  相似文献   

13.
A computer simulation model for the contact between longitudinally-oriented rough surfaces has been formulated. This model closely duplicates the actual surf ace contact deformation behavior by taking into account the elastic interactions between the asperities. There were no assumptions made about the shapes, or any deformation behavior of the asperities, except for their obeying the laws of elasticity. The plastic deformations on the high asperity peaks were taken into account by setting a ceiling on their contact pressures at the material hardness value. The simulations used real surface profiles which were digitized from unworn circumferentially ground steel surfaces. Each pair of these profiles was mathematically combined to form an equivalent rough profile pressing against an infinitely rigid flat and having the appropriately adjusted elastic modulus. A total of 28 different pairs of profiles were used in the simulations. Each contacting pair was subjected to 30 different load levels and the local contact pressures and deformations were calculated. The contact simulations yielded some important mathematical relationships between parameters, such as the real area of contact, average gap, and average asperity load through statistical curve fitting. Two analytical functions were generated to relate the average load to average gap and the real area of contact to load.  相似文献   

14.
针对实际电网存在着大量的三绕组变压器,但国际上一些著名商业软件,如BPA仿真软件、Matpower这一权威潮流计算开源软件,均只提供双绕组变压器模型,限制了其在具有三绕组变压器的电力系统中的应用的问题,潮流计算是自主开发的电力系统各种应用软件的核心模块,因此依托国际权威开源程序进行二次开发,是一种较好的选择。对Matpower要求的数据格式进行了归纳,对变压器的一般的等值电路及带理想变压器的等值电路和带标幺值的等值电路进行了分析研究,提出了三绕组变压器转换为双绕组等效模型的建模方法,使得原先只适应双绕组变压器的潮流计算软件可以适用于三绕组变压器电网的潮流计算;最后以Matpower软件为例进行了案例计算,并用PSASP仿真软件进行对比验证。研究结果证明,所提出的建模方法是有效的。  相似文献   

15.
针对电站锅炉风险等级评价问题,将模糊综合评价技术应用到电站锅炉风险等级评价中。开展了电站锅炉失效影响因素及模糊评价因素的重要程度分析,建立了一套科学合理适于在线评价的电站锅炉风险评价体系,提出了模糊综合评价技术与改进的模糊层次分析法相结合的模糊风险评价方法,利用改进的模糊层次分析法计算了指标体系中各层指标权重。对某一台电站锅炉的实际运行工况影响子因素进行了模糊风险评价,采用模糊合成算子进行模糊综合运算得到电了站锅炉运行工况影响子因素的评价向量。研究结果表明:电站锅炉的运行工况影响子因素的风险评价等级为第6级,失效可能性等级为小,该电站锅炉运行工况良好。  相似文献   

16.
黑棣  郑美茹 《机电工程》2016,(11):1315-1321
针对具有进油孔的有限长滑动轴承油膜力求解问题,采用变分原理和分离变量法,求得了有限长滑动轴承油膜压力分布的近似解析表达式。将油膜压力分布的近似解析表达式在油膜存在区域上进行积分,即得到了油膜力。将提出的计算有限长滑动轴承油膜力方法与无限长轴承模型、有限元方法的计算结果进行了比较,发现了提出的方法与有限元方法的计算结果很接近。最后,研究了进油孔位置和进油压力对油膜存在区域、油膜力等的影响,研究结果表明进油孔位置和进油压力对油膜存在区域和油膜力有较大的影响。  相似文献   

17.
The strength of composite plate with different hole-shapes is always one of the most important but complicated issues in the application of the composite material. The holes will lead to mutations and discontinuity to the structure. So the hole-edge stress concentration is always a serious phenomenon. And the phenomenon makes the structure strength decrease very quickly to form dangerous weak points. Most partial damage begins from these weak points. According to the complex variable functions theory, the accurate boundary condition of composite plate with different hole-shapes is founded by conformal mapping method to settle the boundary condition problem of complex hole-shapes. Composite plate with commonly hole-shapes in engineering is studied by several complex variable stress fimction. The boundary integral equations are founded based on exact boundary conditions. Then the exact hole-edge stress analytic solution of composite plate with rectangle holes and wing manholes is resolved. Both of offset axis loadings and its influences on the stress concentration coefficient of the hole-edge are discussed. And comparisons of different loads along various offset axis on the hole-edge stress distribution of orthotropic plate with rectangle hole or wing manhole are made. It can be concluded that hole-edge with continuous variable curvatures might help to decrease the stress concentration coefficient; and smaller angle of outer load and fiber can decrease the stress peak value.  相似文献   

18.
正3-11 September,2014University of Bologna,Bologna,Italy www.summerscrews.org summerscrews2014.ing.unibo.it SUMMER 20SCREWS 14In 2014,our screw-theory school comes to the world's oldest university.In early September,Summer Screws'14 will gather six experts in the application of screw theory in robotics and up to 40 participants at the University of Bologna,Bologna,Italy.The school will teach attendees how to apply existing methods and empower them to develop new ones in their own research.The basic theoretical notions will be introduced in a rigorous manner,emphasizing examples,applications,and exercises.Scholarships are available.  相似文献   

19.
交通荷载作用下桥梁结构参数识别方法   总被引:2,自引:1,他引:1  
应用动力节点加载法,将作用在桥梁上的交通荷载转化为等效节点荷载,再用两步构造法识别结构物理参数.第1步,用Newmark-β方法变换结构运动方程,并用结构的加速度响应求得变换空间内的位移、速度和加速度响应;第2步,基于最小二乘原理,构造出变换空间内求解结构参数的递推式,进行结构物理参数识别.数值模拟结果表明,在交通荷载作用下,该方法能够快速、准确地进行桥梁结构参数识别.  相似文献   

20.
Taking the actual project of teaching and researching process for example, the relationship between the industrial engineering and product development is discussed. And use the novel visualization technology to support the industrial engineering and product development. How to use the new computer modeling and simulating technologies to support the product development and industrial engineering, is introduced especially. The support includes both domestic products and industrial systems. The visualization and computer technologies take a very important role in some system or multi-direction modeling, those technologies mentioned above can help the industrial engineers study the effect of design on the whole life circle, including the producing steps. So the engineers can avoid making the wrong decision which may cause bad effects on the whole industrial engineering.  相似文献   

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