用石墨炉原子吸收光谱法测定润滑油中的痕量镍

将润滑油、Tween80与1％硝酸溶液三种组分按1．5：3：18的配比制成稳定的微乳液，采用标准加入法，微乳液直接进样(进样量为20μL)，用石墨炉原子吸收光谱法测定了润滑油中的镍。对最佳原子化条件进行了试验。方法的精密度为5．1％，检出限为0．078μg／mL，回收率为95．0％一102．0％。     

锰(Ⅱ)-1-(2-吡啶基偶氮)-2-萘酚-混合微乳液显色体系的研究与应用

文章研究了以阳离子型微乳液 CTMAB/ n- C4H9OH/ n- C7H16/ H2 O与非离子型表面活性剂乳化剂 - OP的混合微乳液为介质 ,Mn( )与 1 - ( 2 -吡啶偶氮 ) - 2 -萘酚( PAN)的显色反应 ,在 p H值 9.0～ 1 0 .0范围内 ,配合物的最大吸收波长为 5 64nm,回归方程 :A=0 .0 30 2 c- 0 .0 0 1 7( c/ μg· 2 5 ml-1) ,相关系数 r=0 .9999,表观摩尔吸光系数为 4.2 9× 1 0 4L·mol-1·cm-1,Mn( )浓度在 0 .39μg· 2 5 ml-1～ 2 0 μg· 2 5 ml-1范围内服从比尔定律 ,检出限 0 .39μg· 2 5 ml-1,相对标准偏差 ( RSD% )在 0 .0 1 4%～ 0 .91 %之间 ,加标回收率在92 .72 %～ 1 1 0 .75 %之间。本法用于铝合金中微量锰的测定 ,结果令人满意。     

微乳液法制备纳米铜粉及其在润滑油中的应用研究

研究了以微乳液法制备纳米铜粉。以CuSO4·5H2 O、NaHBO4、PVP、AES等为主要原料 ,制得粒度可控、经透射电镜检测粒径在 30～ 5 0nm、经X衍射分析为单质铜的铜粉。该铜粉和其他润滑油添加剂进行复配后添加在 5 0 0SN基础油中 ,可以大大提高润滑油的抗磨减摩性能、氧化安定性 ,以 3%的比例加入到润滑油中 ,可以节省燃油达 1 8 71 %。     

微乳液分光光度法在不锈钢餐具镍含量测定中的应用

文章研究了以非离子型微乳液乳化剂 - OP/n- C4H9OH/n- C7H16/H2 O为介质 ,Ni( )与 1 - ( 2 -吡啶偶氮 ) - 2 -萘酚 ( PAN)的显色反应 ,在 p H值 8.5 8～ 1 0 .70范围内 ,配合物的最大吸收波长为 5 70 nm,回归方程 :A=0 .0 31 3c- 0 .0 0 66( c/μg· 2 5 ml-1) ,相关系数 r=0 .9996,表观摩尔吸光系数为 4.5 6× 1 0 4L/( mol·cm) ,Ni( )浓度在 0 .2～ 2 5 μg/2 5 m L范围内服从比尔定律 ,检出限 0 .2 μg/· 2 5 m L,相对标准偏差 ( RSD% )在 0 .0 1 4%～ 0 .64%之间 ,加标回收率在 95 .0 0 %～ 1 1 0 .9%之间。本法用于合成样和不锈钢餐具浸泡液中镍的测定 ,结果令人满意     

原位直接制备纳米铜润滑油及其摩擦学性能研究

以硝酸铜为原料,在100SN,150SN,500SN 3种润滑油基础油微乳液体系中使用原位液相直接制备纳米铜润滑油,使用扫描电镜(SEM)表征制备的纳米铜的表面形貌,使用四球摩擦磨损试验机考察制备的纳米铜润滑油的减摩抗磨和极压性能.结果表明:原位制备的纳米铜颗粒的粒径在20-50 nm之间.在100SN基础油中原位制备的纳米铜润滑油具有较高的承载能力和良好的减摩抗磨性能,可使基础油的最大无卡咬负荷增大27%,在392 N,1 450 r/min条件下,可使基础油的摩擦因数、磨斑直径分别减小3.8%,20%.而在150SN,500SN基础油中原位制备后的纳米铜对润滑油的承载能力没有明显的影响.     

固相微萃取-气相色谱-质谱法测定水中双酚A

基于固相微萃取技术 (SPME)具有前处理方法操作简单、避免使用有机溶剂、回收率高等优点 ,且容易与其它分析仪器联用 ,建立了一种顶空衍生固相微萃取 -气相色谱 -质谱法 (SPME-GC/MS)测定水中双酚 A的分析方法。通过优化 SPME纤维头、萃取温度和时间、解吸时间、搅拌速度、p H值等萃取条件及衍生化温度和衍生化时间等衍生化条件 ,实现了水中痕量双酚 A的快速测定。结果表明 :用 85 μm的聚丙烯酸酯 (PA)萃取涂层对水中的双酚 A萃取效果很好 ,双酚 A在 0 .0 1～ 1 0 0 μg/L的质量浓度范围内 ,线性良好 ,相关系数 >0 .999,方法的检测限为 2 .5 ng/L (S/N =3 ) ,相对标准偏差 (n=7)为 3 .1 3 % ,回收率为 86.3 %～ 95 .6%。     

书讯

1 .《车用润滑油宝典》 ,北京联合润华科技公司 ,中国石化出版社 ,2 0 0 3年 ,15 8元。该书共分 8章 :(1)汽车工业与车用润滑油发展动态 ;(2 )中国车用润滑油市场分析 ;(3)车用润滑油基础油 ;(4 )车用润滑油添加剂 ;(5 )车用润滑油分类与技术指标 ;(6 )车用润滑油最新动向与技术指标 ;(7)车用润滑油的评定———理化指标、模拟试验和台架试验 ;(8)粘度延伸准则和基础油互换准则。2 .《石油产品应用指南》 ,王丙申等著 ,石油工业出版社 ,2 0 0 2年 ,6 8元。该书共分 4章 :(1)石油产品基本知识 ;(2 )石油燃料 ;(3)润滑油 ;(4 )润滑脂。3.《石…     

用同位素稀释电感耦合等离子体质谱法测定海水中的痕量铅

5 -磺基 -8-羟基喹啉用作微柱流动注射在线分离、富集和电感耦合等离子体质谱分析流程中的螯合剂 ,与铅反应生成铅螯合物被硅酸镁吸附剂吸附 ,实现痕量铅的分离、富集。对联用系统的参数如螯合剂用量、淋洗条件、洗脱条件和进样量等进行最优化 ,测定标准水样和加标海水的铅回收率分别为 1 0 1 %和 97.9% ,相对标准偏差为± 0 .98% ,检测限为 0 .2 0 4 μg/ L。可应用于生物、环境等高盐样品中铅的在线分离测定     

火焰原子吸收光谱法测定茶叶中铅铜

本文采用干灰化 盐酸消解试样 ,消解液用火焰原子吸收光谱法测定茶叶中铅和铜。在铅吸收波长 2 1 7 0nm处 ,铅在 0～ 1 0 μg/mL呈现良好的线性关系 ,在铜吸收波长32 4 nm处 ,铜的线性范围为 0～ 5 0 μg/mL ,相关系数γ =0 .9996。以 3SA/S计 ,铅检出限 :0 0 6 μg/mL ;铜检出限 :0 0 0 8μg/mL ;方法精密度RSB <3%。回收率 96 %～ 1 0 2 %。     

微乳液增敏分光光度法测铜的研究

研究了以溴化十六烷基三甲基铵 /正丁醇 /正庚烷 /水组成的微乳液为介质 ,水杨基荧光酮为显色剂 ,Cu(Ⅱ )的光度测定体系。其表观摩尔吸光系数ε =1 .1 4× 1 0 5 L .mol 1.cm 1与CTMAB胶束体系相比较 (ε=9.3× 1 0 4L .mol 1.cm 1)灵敏度提高 2 2 %。方法用于锌白铜和水样分析 ,结果令人满意。     

Minimal Realization of Linear Graph Models for Multi-physics Systems

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...     

INTEGRAL EQUATION METHOD＇S APPLICATION IN HOLE-EDGE STRESS OF COMPOSITE MATERIAL PLATE WITH DIFFERENT SHAPED HOLES

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.     

Non-monotonic material contrast in scanning ion and scanning electron images

30 keV Ga⁺ focused ion beam induced secondary electron (iSE) imaging was used to determine the relative contrast between several materials. The iSE signal compared from C, Si, Al, Ti, Cr, Ni, Cu, Mo, Ag, and W metal layers does not decrease with an increase in target atomic number Z₂, and shows a non-monotonic relationship between contrast and Z₂. The non-monotonic relationship is attributed to periodic fluctuations of the stopping power and sputter yield inherent to the ion–solid interactions. In addition, material contrast from electron-induced secondary electron (eSE) and backscattered electron (BSE) images using scanning electron microscopy (SEM) also shows non-monotonic contrast as a function of Z₂, following the periodic behavior of the stopping power for electron–solid interactions. A comparison of the iSE and eSE results shows similar relative contrast between the metal layers, and not complementary contrast as conventionally understood. These similarities in the contrast behavior can be attributed to similarities in the periodic and non-monotonic function defined by incident particle–solid interaction theory.     

Application of Feature Extraction through Convolution Neural Networks and SVM Classifier for Robust Grading of Apples

This paper proposes a novel grading method of apples,in an automated grading device that uses convolutional neural networks to extract the size,color,texture,an...     

分布动态载荷识别的抗噪处理

针对正交多项式频域法在用多种响应对矩形薄板进行载荷识别中抗噪性较差的问题,综合运用平均法、矩阵预处理和奇异值截断法等方法对之进行改善,并引入空间映射的思想,将该方法的应用范围拓展为复杂的模型.利用仿真算例,证实了该方法具有较好的抗噪性.     

基于MELTAC-N平台的核电厂安全级DCS环网研究与测试

针对工程实践中环网通讯相关问题的处理缺乏理论基础及国产化安全级DCS平台的开发缺乏成熟经验借鉴问题,对基于MELTAC-N平台核电厂安全级DCS环网的软硬件实现进行了研究。提出了安全级DCS环网双环网冗余设计、光切换开关设计等硬件设计方法,以及以RPR协议为基础,采用全数据收发策略的软件设计方法。在CPR1000安全级DCS平台上对安全级DCS环网的可靠性及实时性进行了评价,并进行了容错能力、响应时间及响应时间稳定性测试验证实验。结果表明,基于MELTAC-N平台安全级DCS环网软硬件设计具有较好的容错能力及响应时间稳定性。     

Short-Term Relay Quality Prediction Algorithm Based on Long and Short-Term Memory

The fraction defective of semi-finished products is predicted to optimize the process of relay production lines, by which production quality and productivity ar...     

End-to-End Multiview Gesture Recognition for Autonomous Car Parking System

The use of hand gestures can be the most intuitive human-machine interaction medium.The early approaches for hand gesture recognition used device-based methods....     

The laboratory simulation of abrasive wear

Abrasive wear has long been recognised as one of the most potentially serious tribological problems facing the operators of many types of plant and machinery; several industrial surveys have indicated that wear by abrasion can be responsible for more than 50% of unscheduled machine and plant stoppages. Locating the operating point of a tribological contact in an appropriate operational ‚map’︁ can provide a useful guide to the likely nature and origins of the surface degradation experienced in use, though care must be exercised in choosing the most suitable parameters for the axes of the plot. Laboratory testing of materials and simulations of machine contacts are carried out for a number of purposes; at one level for the very practical aims of ranking candidate materials or surface hardening treatments in order of their wear resistance, or in an attempt to predict wear lives under field conditions. More fundamentally, tests may be aimed at elucidating the essential physical mechanisms of surface damage and loss, with the longer term aim of building an analytical and predictive model of the wear process itself. In many cases, component surface damage is brought about by the ingress of hard, particulate matter into machine bearing or sealing clearances. These may be running dry although, more usually, a lubricant or service fluid is present at the interface. A number of standardised wear test geometries and procedures have been established for both two- and three-body wear situations, and these are briefly described. Although abrasive wear is often modelled as following an ‚Archard’︁ equation (i.e. a linear increase in material loss with both load and time, and an inverse dependence on specimen hardness) both industrial experience and laboratory tests of particularly lubricated contacts show that this is not always the case: increasing the hardness differential in an abrasively contaminated lubricated pair may not always reduce the rate of damage to the harder surface.     

ANGULAR DISTORTION ALLOWABLE VALUE AND ASSESS METHOD OF WELD ON COKE TOWER

A graph as the new engineering method for estimate the safety of bulging deformation of coke tower is proposed. Through stresses analysis of circumferential weld of coke tower and comparing the stresses produced by pressure with heat stress of steady state, residual stress, bending stress produced by both itself weight and wind loads, it showed that the stresses produced by pressure on the angle distortion are the main factor of equivalent stress of the combined stress. After comparing four kinds of stress controlling conditions, the relation to stress with depth of angular distortion, grade of curvature of angular distortion and half of region of angular distortion has been inferred. Graph of deformation allowable value of coke tower for different condition by angular distortion and half of region of angular distortion has been plotted. The five steps for its engineering use have been explained. The lighter the grade of curvature is, the larger of bulge allowance, may be, and the bigger of depth of angular distortion may pose too. For the coke tower with a popular structure of Dg 5 400 mm×28 mm, the result by graph is nearly more than the result of two formulas formed by other research, the error is less than 7.0%. But, the graph can be easily applied to different size of angular distortion.