检索结果-南通市图书馆

Rapid screening and simultaneous quantitation/identification of veterinary drugs in foodstuffs of animal origin via hybrid LC-Q-trap combined with library search

在线全文

学校读者我要写书评

暂无评论

Rapid screening and simultaneous quantitation/identification...

Advances in Thermionic Cathode of Tungsten and Molybdenum

中国化学会第二届全国质谱分析学术报告会

作者： meiling wang Xiaoqing Chen College of Chemistry and Chemical Engineering Central South University

The residues of veterinary drugs in edible tissues cause a risk to human health. To ensure food safety, sensitive and specific analytical methods are necessary for multi-residual analysis of veterinary drugs in food matrices[1]. However, most of the current analytical methods such as enzyme-linked immunosorbent assay, GC-MS and LC-MS, are mainly focused on the known target analytes. Nowadays, the screening of their（un）known metabolites[2,3], synthetic analogs[4], or unapproved new designer drugs[5] is one of the most attractive challenges in this field. In this work, unlike the conventional MRM-based targeted measurement or more sophisticated multidimensional platform toward exhaustive identification, a generic strategy based on LC-QqLIT-MS semi-targeted approach was developed for screening, identifying and quantifying veterinary drugs in various types of sample matrices. Especially, the use of information-dependent acquisition（IDA） combined with enhanced product ion scan（EPI） library implemented on the unit resolution LC–QqLIT set-up allowed the highly robust, selective and sensitive analysis of more inclusive profiles of non-target compounds. Another main advantage of the present methodology is the incorporation of a rather fast, simple, and reliable sample pretreatment procedure--QuE ChE RS. The validation and application results of the method demonstrated its satisfactory overall performance by screening, identifying and quantifying 83 veterinary drugs from 9 different classes of animal tissues. Overall, the integration of QuE ChE RS procedure with LC-QqLIT technique can further increase its capability and applicability for rapid screening and reliable qualitative/quantitative/confirmatory analysis of the target and non-target analytes in a complex sample matrix.

关键词： Multi-residue QuEChERS Triple-quadrupole linear ion trap mass spectrometer Semi-targeted screening

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Rare Metals 2001年第3期20卷 137-141页

作者： Jinshu wang,meiling Zhou, Tieyong Zuo, Juan Liu, Jiuxing Zhang, Zuoren Nie The Key Laboratory of Advanced Functional Materials, Ministry of Education, School of Materials Scence and Engineering, Beijing Polytechnic University, Beijing 100022, China Beijing Polytech Univ Sch Mat Sci & Engn Minist Educ Key Lab Adv Funct Mat Beijing 100022 Peoples R China

Several kinds of tungsten thermonic cathodes have been introduced. As a promising alternative for thoriated tungsten, rare earth doped molybdenum cathode has been studied. Compared with the traditional thoriated tungsten, La-Mo cathode has higher emission current density at lower temperature, but it has poor emission stability. In order to improve the emission stability, systematical study on the emission mechanism of La-Mo cathode has been carried out. The life of La-Mo cathode has been improved and has achieved 1400 It, which exceeds the minimum life for practical uses (1000 h). As another alternative for thoriated tungsten cathode, Y-Mo cathode has shown better performance. The thermionic emission capability of Y-Mo cathode is between that of La-Mo cathode and Th-W cathode.

关键词： tungsten molybdenum thermonic cathode emission

在线全文

学校读者我要写书评

暂无评论

冷却速度对金属玻璃性能的影响

稀有金属材料与工程 2016年第12期45卷 3255-3261页

作者：王美玲王庆梅惠希东北京科技大学国家材料服役安全科学中心北京100083 北京科技大学新金属材料国家重点实验室北京100083

采用单辊真空薄带技术和真空吸铸法分别制备了相同成分的金属玻璃薄带和块体金属玻璃。通过示差扫描热分析(DSC)、X射线衍射(XRD)、高分辨透射电子显微镜(HRTEM)和纳米力学探针(Nano Indenter)等技术研究了冷却速度对金属玻璃的组织结... 详细信息

采用单辊真空薄带技术和真空吸铸法分别制备了相同成分的金属玻璃薄带和块体金属玻璃。通过示差扫描热分析(DSC)、X射线衍射(XRD)、高分辨透射电子显微镜(HRTEM)和纳米力学探针(Nano Indenter)等技术研究了冷却速度对金属玻璃的组织结构、热稳定性及力学性能的影响。结果表明:快速冷却得到的金属玻璃薄带和相同成分以较慢的冷却速度制备的块体金属玻璃相比,短程有序结构(SRO)的晶体结构相同,但数量较少,且自由体积含量相对较多;组织结构的差异导致金属玻璃薄带比块体金属玻璃有着更高的热稳定性、屈服强度,弹性模量和硬度。

关键词：金属玻璃热稳定性冷却速度短程有序结构

Study on lipidomic biomarkers of sleep disorders during pregnancy based on lipidomics

在线全文

学校读者我要写书评

暂无评论

Study on lipidomic biomarkers of sleep disorders during preg...

A Survey on Amphibious Robots

第八届泛环渤海生物化学与分子生物学会2018年学术交流...

作者： meiling wang Menjie Li 李存保 Inner Mongolia Medical University

Objective: The fetus’ s need for nutrients increases during pregnancy. A large amount of fat accumulates during the third trimester, and the physiological processes of lipid metabolism may change significantly. Sleep disorder is a common complaint of pregnant women, including insomnia, nighttime awakening and daytime sleepiness. The previous study found that sleep disorders has an important effect on lipid metabolism. Therefore, the lipidomics study on pregnant women with sleep disorders will help further explore the mechanism of sleep disorders during pregnancy. Cerebrospinal fluid(CSF) may be the perfect sample to progress studies in the brain. However there is currently a lack of lipidomic studies of CSF samples for pregnant women with sleep disorders. This study investigated the differences between lipid metabolisms in CSF of pregnant woman with and without sleep disorders to find potential lipid biomarkers closely related to sleep disorders in pregnant women, and explored the relationship of lipid metabolisms in CSF to blood lipids and blood glucose in pregnant women. Methods: A total of 135 females cesarean-section women(n=88 group without sleep disorders and n=47 group with sleep disorders) in Northern hospitals were recruited and the Pittsburgh sleep quality index(PSQI) scale was completed in 24 hours before surgery to assess sleep quality of one month. 1 ml CSF during cesarean section was collected to detect lipid metabolites in it by Ultra-performance Liquid Chromatography-mass spectrometry(UPLC-MS), and 3 ml venous blood in one day before surgery were extracted to detect blood lipids and blood glucose. Results: 1. Supervised data analysis of two-dimensional arrays by orthogonal projections to latent structures discriminant analysis(OPLS-DA), and the model fit analysis was performed to evaluate the differences of lipids in CSF of pregnant woman by score plots and S-plot. Forty-nine lipid molecules with a variable importance projection(VIP) value of >1 were

关键词： Lipidomics Sleep disorders Pregnant women Lipid metabolism

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

A Survey on Amphibious Robots

基于广义PI逆模型的超精密定位平台复合控制

第37届中国控制会议

作者： Ziyi Guo Tao Li meiling wang School of Engineering Science University of Science and Technology of China Institute of Advanced Manufacturing Technology Hefei Institutes of Physical Science

In recent years,amphibious robots are becoming one of the research hotspots,due to their unique advantages of strong environmental adaptability and wide application prospect,which make them have great research *** paper introduces the research status of amphibious robots mainly from the aspects of bionic mechanisms,motion modes and ***,merits and drawbacks of some selected representative robots are *** addition,existing technical problems and difficulties in the research of amphibious robots are ***,because triphibious robots have the highest research value,development prospects of this kind of robots are discussed with the aim to provide valuable information for the research of triphibious ***,assumptions and future work are proposed for the research of triphibious robots.

关键词： Mobile robots Amphibious robots Triphibious robots Bionic mechanisms Motion modes

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

机械工程学报 2015年第2期51卷 198-206页

作者：田艳兵王涛王美玲北京理工大学自动化学院北京100083 青岛理工大学自动化工程学院青岛266520

为了提高超精密定位系统的定位精度和行程,设计一种新型的单级驱动气动伺服定位平台。以金属波纹管为执行机构,以气浮导轨支撑,研究无摩擦条件下的较大行程的精密控制。为减少建立PI模型时的算子数量,减小求逆过程的计算量,提高建模精度... 详细信息

为了提高超精密定位系统的定位精度和行程,设计一种新型的单级驱动气动伺服定位平台。以金属波纹管为执行机构,以气浮导轨支撑,研究无摩擦条件下的较大行程的精密控制。为减少建立PI模型时的算子数量,减小求逆过程的计算量,提高建模精度,改进基本迟滞算子,建立基于广义迟滞算子的广义PI模型,并对模型进行验证。给出广义PI模型的求解析逆方法。设计基于广义PI逆模型的复合控制方案,并进行试验研究。结果表明,基于广义逆模型的阶跃响应系统的定位精度达到30 nm,锯齿波和复频跟踪试验输入下,基于PI逆模型的跟踪精度平均误差为0.96μm和0.63μm,基于广义PI逆模型的跟踪精度平均误差为0.49μm和0.45μm。试验数据表明改进广义PI模型对于增加系统定位精度有效。

关键词：广义迟滞波纹管超精密复合控制

在线全文

学校读者我要写书评

暂无评论

電子期刊對學術圖書館技術服務的影響

现代图书情报技术 2006年第3期 6-14页

作者：王梅玲政治大學圖書資訊與檔案學研究所臺北11605

主要圖館角色與功能的觀點,探討電子期刊為學術圖館技術服來的影響,首先析述電子期刊學術傳播與出版新變革;其次,圖館技術服層面探討電子期刊對館藏發展、資訊組織與位保存三方面影響。最後,總結未來電子期刊技術服... 详细信息

主要圖館角色與功能的觀點,探討電子期刊為學術圖館技術服來的影響,首先析述電子期刊學術傳播與出版新變革;其次,圖館技術服層面探討電子期刊對館藏發展、資訊組織與位保存三方面影響。最後,總結未來電子期刊技術服發展的方向並提供建議。

关键词：电子期刊学术图书馆技术服务馆藏发展资讯组织数位保存

美国I-Schools运动带给台湾图书信息学教育的省思

在线全文

学校读者我要写书评

暂无评论

图书情报工作 2007年第4期51卷 10-15页

作者：王梅玲政治大学图书信息与档案学研究所

藉由与美国华盛顿大学信息学院Harry Bruce院长的对谈及文献探讨,研究下列三项议题:①图书信息学门的名称与定位,即图书信息学教育是图书馆学教育?信息教育?或图书信息学教育?②美国I-Schools运动的意义与内涵;③对台湾图书信息学教育... 详细信息

藉由与美国华盛顿大学信息学院Harry Bruce院长的对谈及文献探讨,研究下列三项议题:①图书信息学门的名称与定位,即图书信息学教育是图书馆学教育?信息教育?或图书信息学教育?②美国I-Schools运动的意义与内涵;③对台湾图书信息学教育的启示。

关键词： I-Schools 信息学院图书信息学教育台湾省信息教育图书馆情报学教育

新中国·新时期·新时代:社会主要矛盾的演进理路及逻辑

在线全文

学校读者我要写书评

暂无评论

东南学术 2019年第3期 9-16页

作者：王美玲首都师范大学马克思主义学院

新时代我国社会主要矛盾发生了变化,但对于其的解读存在一些歧义和误读,如何科学地解释这些问题,需要深入分析新中国、新时期、新时代社会主要矛盾的演进理路及逻辑。社会主要矛盾的演进理路为:新中国—政治敌对矛盾,新时期—经济供需矛... 详细信息

新时代我国社会主要矛盾发生了变化,但对于其的解读存在一些歧义和误读,如何科学地解释这些问题,需要深入分析新中国、新时期、新时代社会主要矛盾的演进理路及逻辑。社会主要矛盾的演进理路为:新中国—政治敌对矛盾,新时期—经济供需矛盾,新时代—社会供需矛盾。社会主要矛盾的演进逻辑包括理论逻辑、价值逻辑和实践逻辑。科学地把握这一演进理路和演进逻辑,对于推进新时代中国特色社会主义事业发展具有重要意义。

关键词：新时代社会主要矛盾演进理路演进逻辑