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Tool Path Generation for clean-up Machining of Impeller by Point-searching Based Method

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Chinese Journal of Aeronautics 2012年第1期25卷 131-136页

作者： TANG Ming ZHANG Dinghua LUO Ming WU Baohai The Key Laboratory of Contemporary Design and Integrated Manufacturing Technology Ministry of EducationNorthwestern Polytechnieal UniversityXi'an 710072China

Machining quality of clean-up region has a strong influence on the performances of the impeller. In order to plan clean-up tool paths rapidly and obtain good finish surface quality, an efficient and robust tool path generation method is presented, which employs an approach based on point-searching. The clean-up machining mentioned in this paper is pencil-cut and multilayer fillet-cut for a free-form model with a ball-end cutter. For pencil-cut, the cutter center position can be determined via judging whether it satisfies the distance requirement. After the searching direction and the tracing direction have been determined, by employing the point-searching algorithm with the idea of dichotomy, all the cutter contact （CC） points and cutter location （CL） points can be found and the clean-up boundaries can also be defined rapidly. Then the tool path is generated. Based on the main concept of pencil-cut, a multilayer fillet-cut method is proposed, which utilizes a ball-end cutter with its radius less than the design radius of clean-up region. Using a sequence of intermediate virtual cutters to divide the clean-up region into several layers and given a cusp-height tolerance for the final layer, then the tool paths for all layers are calculated. Finally, computer implementation is also presented in this paper, and the result shows that the proposed method is feasible.

关键词： NC machining impellers tool path clean-up point-searching

A disposable paper-based thin-layer chromatography sample clean-up approach for the sensitive determination of trace diethylstilbestrol residues in aquatic products

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A disposable paper-based thin-layer chromatography sample cl...

clean-up System在混合斑DNA提取中的应用

第三届全国质谱分析学术报告会

作者： Feng Li Jue Sun Linjiang Pang Hexiang Jia Yuming Zhong Wenjie Zhao Yiming Zhang

In this study,a rapid clean-up approach to the preparation of aquatic food samples based on disposable thin-layer chromatography(d TLC)was ***,plates with uniform brushed Gelatin 60 as the stationary phase on paper coated with polyvinyl chloride(PVC)were designed and fabricated ***(DES,mixture of cis and trans isomers),which was selected as a typical trace residue of an illegal contaminant in aquatic products,can be perfectly separated on the paper-based slide under the optimized solvent development *** the target compounds are all located in a rather narrow zone,the target zone of the slide can easily be cut out according to the mark on the back of the slide,and the target compounds can be re-extracted from the slide with organic *** final extraction derivatives were detected by gas chromatography coupled with mass spectrometry(GC-MS).Under the optimized analytical conditions,GC-MS can be used to detect trace amounts of DES in aquatic products without obvious *** analytical linearity of DES ranged from 1.0μg kg to 0.20 mg kg,with a detection limit of 0.20μg *** method not only effectively circumvents the labor-intensive clean-up work and substantial solvent consumption of typical methods but also effectively eliminates the interference effects from co-existing matrix materials in complex ***,the present work demonstrated the reliability and applicability of paper-based d TLC slides as a clean-up method for the analysis of food contaminants in the future.

关键词： Thin-layer chromatography clean-up Diethylstilbestrol GC-MS Food analysis

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刑事技术 2008年第4期33卷 63-64页

作者：徐晓宁匡金枝孙世平王玉健天津市公安刑事侦查局刑科所 300193

强奸案生物物证鉴定中经常遇到混合斑检材的DNA检验，作者在日常检验中用clean-up System（promega公司产品）替代混合斑差异裂解后的有机法提取步骤，效果良好，报道如下。

关键词： DNA 混合斑 clean-up system

怎样使用新版本的计算机解毒工具clean—up?

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电脑与微电子技术 1994年第3期 55-56页

作者：马轮基广西壮族自治区气象台南宁530022

计算机病毒是当今信息社会的一大发展障碍,最新的资料表明,计算机病毒的种类已经超过5000种,越来越多的人备受困扰。及时地清除计算机病毒的感染,既是减少危害的一种“亡羊补牢”的有效方法,又是防止计算机病毒进一步蔓延和扩大危害的... 详细信息

计算机病毒是当今信息社会的一大发展障碍,最新的资料表明,计算机病毒的种类已经超过5000种,越来越多的人备受困扰。及时地清除计算机病毒的感染,既是减少危害的一种“亡羊补牢”的有效方法,又是防止计算机病毒进一步蔓延和扩大危害的重要手段。目前,专门的计算机解毒工具种类很多,clean—up是其中较为常用的一种。为了更准确的理解和使用这一工具,下面根据其新版本的有关资料节译出关键内容供大家参考。译者水平有限。

关键词：计算机病毒解毒工具 clean-up

Evaluation of Sources and Options for Possible clean up of Anthropogenic Mercury Contamination in the Ankobra River Basin in South Western Ghana

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Journal of Environmental Protection 2011年第10期2卷 1295-1302页

作者： Thomas Mba Akabzaa Sandow Mark Yidana 不详

The study assesses the spatial distribution and sources of mercury contamination in the Ankobra River Basin in southwestern Ghana and discusses possible remediation options and challenges. Eighty-two (82) samples of water and streambed sediments from areas of active and historic artisanal mining and historic mine spoil from large-scale mining were analysed for their total mercury content using cold vapour Atomic Fluorescence Spectrometry (CV-AAS). The highest Hg concentrations were recorded from historic mine tailings, legacy of large scale mines in the area, which averaged 795 ppb but ranged from 80 ppb to 2500 ppb. Concentrations in streambed sediments averaged 139 ppb, but ranged from 63 ppb to 270 ppb. Water, expectedly, gave the lowest Hg concentrations with a mean value of 1.5 ppb, but ranged from below detection to 8 ppb. Areas worked by artisanal miners and historic tailings dumps at Bondaye and Prestea recorded the highest mercury values. These high mercury concentration sites constitute potential sources of major mercury pollution in the area and therefore require major and urgent clean up to mitigate any major health risks. However, any remediation strategy would require further and detailed study of the contaminated sites and an evaluation of known remediation techniques to achieve maximum results.

关键词： Ankobra Basin Mercury Contamination clean-up Old Tailings Sediments Water

Economic Evaluation of the UCSRP-HP Process in IGCC Applications

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International Journal of clean Coal and Energy 2013年第3期2卷 25-34页

作者： Arunabha Basu Ajay Makkuni S. James Zhou Howard S. Meyer Energy Conversion Gas Technology Institute Des Plaines USA

With financial assistance from the US Department of Energy and the Illinois clean Coal Institute, Gas Technology Institute (GTI) has been working with the University of California, Berkeley, for further development of their UCSRP-HP (University of California Sulfur Recovery Process-High Pressure) technology. The key focus of the UCSRP-HP technology is integrated multi-contaminant removal of hydrogen sulfide (H2S), carbonyl sulfide (COS), ammonia (NH3), chlorides and heavy metals present in coal-derived syngas. The process has two major components: 1) removal of various trace components with a solvent (e.g., diethylene glycol or water) using a high-pressure scrubbing unit and 2) removal of H2S as sulfur via reaction with SO2 (in the presence of a solvent mixed a small quantity of a homogeneous catalyst) at 120?C to 150?C and at any syngas pressure. During this research, data critical to developing and evaluating UCSRP-HP technology for multi-contaminant removal from syngas derived from Illinois #6 coal were obtained. In this paper, we have presented key economic evaluations of the UCSRP-HP process, including potential integrations with other technology options for CO2 and hydrogen separations, for a nominal Illinois #6-coal-based 550-MWe Integrated Coal Gasification Combined Cycle (IGCC) facility with CO2 capture and sequestration. GTI is exploring various options to demonstrate this technology in a pilot plant using actual syngas from a coal gasifier.

关键词： UCSRP-HP Technology IGCC Power Plants Synthesis Gas clean-up IGCC Economics Carbon Capture and Sequestration

High Performance Liquid Chromatographic Identification and Estimation of Phthalates in Sewer Waste and a Receiving River in Ibadan City, Southwestern Nigeria

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Journal of Water Resource and Protection 2012年第10期4卷 851-858页

作者： Gregory O. Adewuyi Department of Chemistry University of Ibadan Ibadan Nigeria

Medical wastes have been implicated in river pollution in developing countries and most often people depend on water from such rivers for sources of livelihood. Phthalates (endocrine disruptors) are major components in medical wastes and are commonly found contaminants in aquatic environment. Most sewage treatment facilities handling medical waste are inefficient due to overuse and poor maintenance and discharge directly into rivers. This study aimed to investigate the identity and estimates the concentration of phthalates in supposed treated medical wastes from a hospital sewer and water from a receiving river. Samples were randomly collected before and after treatment by the sewer plants, while samples were randomly collected along the course of the river starting from point of discharge. Control samples were taken from upstream about 500 m along the river course. The samples were extracted by liquid-liquid chroma- tographic process using dichloromethane, after which they were cleaned up in a column of silica gel using hexane as the mobile solvent. The cleaned extracts were analyzed by HPLC. The concentrations (μg/L) of dimethyl-, diethyl-, diphenyl-, dibutyl- and di-(2-ethyl)hexyl phthalates ranged from 62.81 ± 18.53;4.74 ± 3.57;2.05 ± 1.80;11.40 ± 5.58 to 141.92 ± 35.8 respectively in the sewer waste. The receiving river had a concentration (μg/L) of 9.17 ± 14.02;0.18 ± 0.31;0.48 ± 0.84;2.84 ± 1.21;61.72 ± 38.35 respectively for dimethyl-, diethyl-, diphenyl-, dibutyl- and di-(2-ethyl) hexyl phthalates. These concentrations were higher than control and far exceeded the USEPA limits of 3 μg/l recom- mended for phthalates in water. Contaminants of aquatic environment by untreated wastes from hospitals has serious implications on public health and environment as human risks for phthalate esters downstream are high and this calls for urgent need to develop strategy to build incentives for compliance in treatment and discharge of wastes into river waters.

关键词： Sewage Treatment Phthalates Liquid-Liquid Extraction clean-up Effluent Toxicity