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151.
社会化进程的快速发展,加速我国用电的使用,使我有成为了用电大国,而在用电过程中,则要确保电力系统的安全与发展。特别是物质生活不断富足的当下,用电需求与日俱增,用电量不断增长,然而,在我国诸多用电因素影响之下,要对我国电力系统进行广泛的研究,特别是对智能电网在电力技术中的运用研究,这样才能对我国电力系统进行规范化应用,提升我国用电的安全性。  相似文献   
152.
计算光度法同时测定人发中的锌铜铁   总被引:5,自引:0,他引:5  
本文对5-溴-(二乙基氨基-2-(2-哟啶偶氮)苯显色剂,用多元线性回归或卡尔曼滤波法处理多波长测量数据数据,在pH5.11的30%乙醇介质中同时测定了人发中的锌、铜和铁。  相似文献   
153.
赵培庆  宫照阳 《分子催化》1997,11(6):427-432
全过程合成出手性双膦配体2,2’-双(二苯基膦)-6,6’-二甲基联苯,以金属钌为中心原子,制备出几种不对称催化剂。通过考察不对称氢化制备(S)-(+)-萘普生的反应光学收率,研究了催化剂的催化性能,并与联萘型双膦配体催化剂进行了比较。  相似文献   
154.
适合低PH范围测量的新型中性载体膜PH电极的研究   总被引:2,自引:0,他引:2  
柴雅琴  吴朝阳 《分析化学》1995,23(11):1252-1255
本文设计合成了一种在低PH范围对氢离子有很好Nernst响应的新型中性载体-N,N-二辛基菸酰胺,并把它制成PVC膜PH电极,测试了该电极的线性范围、选择性、稳定、重现性和内阻等各项性能参数,并试验了电极抗氢氟酸腐蚀的能力,该该电极用于氢氟酸的电离常数测定时获得了满意的结果。  相似文献   
155.
磷与碳、硅、硼、铝形成的二元簇离子的激光产生   总被引:3,自引:0,他引:3  
在自制的装置上,用高能密度的脉冲激光束在高真空中直接溅射红磷和碳、硅、硼或铝粉的混合物,通过激光等离子体反应,产生了十分丰富的XnPm±(X=C,Si,B,Al)二元原子簇,记录了它们的飞行时间质谱.对这些簇离子组分的分析发现,它们的成键和结构因其组成元素的不同而有明显的差异,这些差异反映了它们独特的结构化学行为.  相似文献   
156.
Scientific applications are often not written with multiprocessing, cluster computing or grid computing in mind. This paper suggests using Python and PyCSP to structure scientific software through Communicating Sequential Processes. Three scientific applications are used to demonstrate the features of PyCSP and how networks of processes may easily be mapped into a visual representation for better understanding of the process workflow. We show that for many sequential solutions, the difficulty in implementing a parallel application is removed. The use of standard multi-threading mechanisms such as locks, conditions and monitors is completely hidden in the PyCSP library. We show the three scientific applications: kNN, stochastic minimum search and McStas to scale well on multi-processing, cluster computing and grid computing platforms using PyCSP.  相似文献   
157.
The personal capabilities and intentions of employees indicate their performance within their organization. It is important for the organization to capture this kind of tacit knowledge since the workforce are the true experts in perceiving the organization's current reality and evaluating which assets require development – including themselves as knowledge assets. The collective inner voice of the workforce helps the organization's management to steer the company and its assets in a sustainable direction.This article presents how the collective inner voice of the workforce can be captured and how it can be used for the benefit of the organization and its employees. The objective is to support individuals’ personal aspirations, as well as to save the money, time and resources that an organization spends on personnel training.The focus of this article is on demonstrating a possible soft-computing method used for competency simulation. The process starts with a linguistic self-evaluation conducted by employees, where individuals’ own perception of current and target competence levels is captured. The self-evaluation is conducted with the help of fuzzy logic. Clusters are formed from the result dataset using an unsupervised neural network clustering method: self-organizing maps. A demonstrator tool is then used to perform a “what-if” type of analysis/simulation on the clusters in the results. With the demonstrator tool, employees can roughly test the impact of alternative training scenarios for themselves. For individuals this may open up new directions for self-development, and for organizations this may allow the efficient use of training resources. We tested the approach with a dataset from a real human resource development project among nuclear power plant operators.The case study reveals the potential of soft-computing based collective competency simulation as one part of personnel development projects in the future. Yet the techniques and the demonstrator tool used in this experiment are far from being products that employees could easily use as part of their training project. Possible benefits of the proposed approach are demonstrated in this article.  相似文献   
158.
159.
A simple, rapid, and environmentally friendly method was developed for the determination of acrylamide and trimethylolpropane in paper packaging materials. No organic solvent was used and the matrix effect was investigated. The extract was directly analyzed by liquid chromatography with tandem mass chromatography for quantification and confirmation. The chromatographic separations were performed on a ZORBAX HILIC Plus (2.1 mm × 150 mm, 3μm; Agilent, USA) column with only one mobile phase (100% water). Calibration curves for acrylamide and trimethylopropane were achieved with concentrations ranging from 0.4 to 20 mg/kg and the corresponding r2 values were 0.998 and 0.999, respectively. The recoveries were >85% with relative standard deviations <10%. The validated method was applied to the analysis of 50 real samples, and positive results were obtained for 30 samples. The result indicated that trimethylolpropane is associated with inks and printing activity and acrylamide is widely used as a papermaking additive in many paper packages. The concentrations of acrylamide and trimethylolpropane ranged from 0.41 to 7.5 and 0.50 to 8.8 mg/kg, respectively. The results of this study revealed that this method could be used accurately and precisely.  相似文献   
160.
广东科学中心交通世界展馆的高温超导磁悬浮车演示模型,由支架、永磁轨道、超导磁悬浮小车、直线电机和控制系统构成。∞形轨道长19m,包含直线、圆曲线、缓和曲线、坡道,轨道沿线布置直线电机线圈和光电传感器。磁悬浮小车为两节联挂,每节小车车体由两个低温液氮容器和一个直线电机动子组成,每个液氮容器中包含6块YBCO超导块材。磁悬浮小车可以在轨道上连续运行,自控系统能够对小车进行启动、加速、减速、定位停车等运行控制,运行模式分自动行驶和手动操作两种。  相似文献   
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