离子色谱电导检测器测定酱腌菜中的亚硝酸盐和硝酸盐

本文建立了一种用离子色谱-电导检测器测定酱腌菜中亚硝酸盐和硝酸盐的方法.样品经超声提取、固相革取柱净化、ionPac AS19色谱柱分离,以梯度洗脱方式,用电导检测器检测.用该方法硝酸盐和亚硝酸盐的检出限为0.03mg/kg和0.05mg/kg,方法精密度小于5％,回收率大于90％.适用于酱腌菜等高含盐量食品的亚硝酸盐和硝酸盐测定.     

直接电导检测离子排斥色谱法测定酱油中的有机酸

研究了直接电导检测离子排斥色谱法分离测定酱油中多种有机酸.以Shim-pack SCR-102H柱为分离柱,选用对甲苯磺酸和乙腈为淋洗液,考察了淋洗液浓度、色谱柱温度及淋洗液中乙腈含量对分离和测定有机酸的影响.通过实验确定最佳的色谱条件2 mmol/L p-甲苯磺酸乙腈(v/v,91/9)淋洗液,流速1.0 mL/min,柱温50℃.方法对所测有机酸的检出限在0.06～1.05 mg/L之间,相对标准偏差在3.3%以下(n=5),加标回收率在96.5%～100.6%之间.     

蒸馏法前处理联用离子色谱测定水体基质中氨氮

建立了一种用蒸馏法富集水体样品中氨氮并联用离子色谱技术检测的方法。该方法可以有效富集水体中的氨氮（以NH4＋形式）,并去除水体样品中的Na＋、K＋及其他基质离子的影响。以IonPac CS16色谱柱为分离柱,用甲磺酸等度洗脱方式使待测组分分离,流速为1mL/min,电导检测,外标法定量。在优化后的实验条件下,NH4＋的线性范围为0.01-50μg/mL,相关系数大于0.9991;将该方法应用于海水、湖水、苦咸水等水样的检测,实际样品加标回收率为86.8-106.8%,检测限为1.28ng/mL（信噪比S/N=3）。实验结果表明,该方法可以用于水体中氨氮的检测。     

阀切换技术-离子色谱法测定水产品中的硼酸盐

建立利用阀切换技术,离子排斥-抑制电导检测器测定水产品中硼酸盐的离子色谱方法。样品经过简单的除蛋白前处理,即可进样分析。采用ICS-1600离子色谱仪(配十通阀),IonPac ICE-Borate离子排斥柱分离,利用阀切换技术,IonPacTBC-1硼酸盐富集柱在线捕获待测成分的同时去除基体干扰,而后进行二次分离。2.5mmol/L MSA+60mmol/L Mannitol作为淋洗液,流速1.0 mL/min,进样量100μL,抑制电导检测。在上述色谱条件下,硼酸的质量浓度在0.1~5.0μg/mL时与色谱峰面积(A)之间的线性关系良好,检出限(S/N=3)为0.02μg/mL。将本方法应用于水产品中硼酸盐的检测,加标回收率为86.5%~93.0%。该方法在线去除基体干扰,简便、快速、准确,可用于实际样品的测定。     

直接电导检测-离子排斥色谱法测定碳酸氢根

发展了直接电导检测一离子排斥色谱测定碳酸氢根的方法。以Shim-pack SCR-102H离子排斥色谱柱为分离柱,选用对羟基苯甲酸为淋洗液,考察了淋洗液浓度、流速、色谱柱温度对碳酸氢根保留时间的影响。确定最佳色谱条件为：以0．1mmol／L对羟基苯甲酸为淋洗液,流速1．0mL／min,色谱柱温度40℃。在此条件下,碳酸氢根的保留时间在12min之内,检出限（S／N=3）为0．8mdL,连续5次测定峰面积的相对标准偏差为0．4％。将方法应用于可乐样品的分析,加标回收率为96．5％。     

阀切换技术-离子色谱法测定水产品中瞰明酸盐

建立利用阀切换技术,离子排斥．抑制电导检测器测定水产品中硼酸盐的离子色谱方法．。样品经过简单的除蛋白前处理,即可进样分析采用ICS-1600离子色谱仪（配十通阀）,IonPacICE．Borate离子排斥柱分离,利用阀切换技术,lonPacTBC-1硼酸盐富集柱在线捕获待测成分的同时去除基体干扰,而后进行二次分离、2．5mmol／LMSA＋60mmol／LMannitol作为淋洗液,流速1．0mL／min,进样量100uL,抑制电导检测。在上述色谱条件下,硼酸的质量浓度在0.1--5．0ug／mL时与色谱峰面积（A）之间的线性关系良好,检限（S／N=3）为0．02ug／mL。将本方法应用于水产品中硼酸盐的检测,加标回收率为86．5％～93．0％。,该方法在线去除基体干扰,简便、快速、准确,可用于实际样品的测定.     

离子色谱法测定瓜子中的二氧化硫残留

建立了离子色谱-抑制型电导测定瓜子中的二氧化硫残留量的方法。样品经由水蒸气蒸馏,通过3%双氧水吸收氧化得到待测液,再通过0.22μm滤膜和C18柱处理后,用IonPac AG11-HC(4*50mm)+IonPac AS11-HC(4*250mm)分离柱,1.0mL/min KOH淋洗液梯度洗脱,抑制电导检测。在优化色谱条件下,二氧化硫残留量在一定范围内线性良好,检出限为0.059mg/kg。加标回收率在88.78%~98.13%之间。该方法灵敏度高,重现性好,测定结果可靠。     

用涂渍聚丁二烯马来酸固定相的离子色谱分析过渡金属离子

分析过渡金属离子的传统方法是阳离子交换色谱或离子对色谱法，二价金属离子是在磺酸型阳离子交换剂色谱固定相上进行分离，用各种洗脱剂洗脱和电导检测器进行检测，但是这种检测方法对过渡金属离子不够灵敏，通常使用的方法是ＵＶ－Ｖｉｓ检测和用有吸收基团的进行柱前或柱后衍生物，这样中以得到较好的分离度和灵敏度，但这一方法繁琐复杂。本文阐述了一种在涂渍聚丁二烯马来酸的固定相上分离过渡金属的方法，这一固定相普成功地用     

离子排斥色谱法分析饮用矿泉水中总碳酸盐

利用阳离子交换分离柱对弱酸阴离子具有离子排斥作用这一分离机理,以稀盐酸(0.1mmol/L)为淋洗液,抑制型电导检测,直接进样快速测定饮用矿泉水中的碳酸盐.结果显示,该方法具有良好的线性(r=0.99999)和精密度(0.4336％,n=l0),回收率为99.1％～103.52％,最小检出浓度为0.86mg/L.     

AQF-离子色谱联用技术检测1,4-丁炔二醇中全氯

介绍了一种全新的“油相”样品前处理仪器--自动快速燃烧炉（AQF）与离子色谱联用技术,测定1,4-丁炔二醇中全氯的方法.选择色谱条件为：AS14A离子色谱分离柱,碳酸钠/碳酸氢钠缓冲溶液等度淋洗,抑制型电导检测.样品经过AQF装置分段燃烧约10分钟后,在线进入离子色谱系统进行分析.该方法的检测限（S/N=3）为60 μ g/L,线性相关系数r=0.9997,RSD为2.9%,回收率为100-104%,具有灵敏度高,选择性好,操作简单,节省时间,对环境友好等特点,用于实际样品的检测,所得结果令人满意.     

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.