Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99


Any time

2020 ( 27 )

2019 ( 114 )

2018 ( 765 )

2017 ( 790 )

Custom range...

Search Results: 1 - 10 of 61052 matches for " Ajuan Yu "
All listed articles are free for downloading (OA Articles)
Page 1 /61052
Display every page Item
Rapid and Sensitive Analysis of Eight Polyphenols in Tobacco by Rapid Resolution Liquid Chromatogarphy  [PDF]
Fuwei Xie, Ajuan Yu, Dengke Hou, Huimin Liu, Li Ding, Shusheng Zhang
American Journal of Analytical Chemistry (AJAC) , 2011, DOI: 10.4236/ajac.2011.28107
Abstract: A rapid resolution liquid chromatographic (RRLC) method for the determination of eight polyphenols in to-bacco was developed. Polyphenols were extracted from tobacco samples by methanol/ water in an ultrasonic bath, then subjected to clean up by solid phase extraction. The separation was performed on a 50 × 4.6 mm, 1.8 μm ZORBAX Eclipse XDB-C18 column. Compared with conventional HPLC method, the analysis time for eight polyphenols by RRLC method was reduced from 20 to 5 min without sacrificing resolution, and the sensitivity was improved. This method appears simple, accurate and precious. The relative standard devia-tions (RSD) of overall analysis procedure for eight tobacco polyphenols were less than 2% with the recover-ies ranging from 94% to 107%. This method could be applied to the rapid determination of major polyphe-nols in tobacco with satisfactory results.
A Feasible SQP Method with Superlinear Convergence for General Constrained Optimization
Ajuan Ren,Fujian Duan,Zhibin Zhu,Zhijun Luo
Journal of Applied Sciences , 2007,
Abstract: In this study, optimization problems with general equality and inequality constraints are discussed. Firstly, the original problems are changed into parametric programming problems with only inequality constraints and these two problems are equivalent with each other if the parameter is suitable. Then, we give a new idea called first-order feasible condition, which is used to solve the changed problems. Under some reasonable conditions, the global and superlinear convergence is shown.
A Training effect on electrical properties in nanoscale BiFeO$_3$
Sudipta Goswami,Dipten Bhattacharya,Wuxia Li,Ajuan Cui,QianQing Jiang,Chang-zhi Gu
Physics , 2013, DOI: 10.1088/0957-4484/24/13/135705
Abstract: We report our observation of the training effect on dc electrical properties in a nanochain of BiFeO$_3$ as a result of large scale migration of defects under combined influence of electric field and Joule heating. We show that an optimum number of cycles of electric field within the range zero to $\sim$1.0 MV/cm across a temperature range 80-300 K helps in reaching the stable state via a glass-transition-like process in the defect structure. Further treatment does not give rise to any substantial modification. We conclude that such a training effect is ubiquitous in pristine nanowires or chains of oxides and needs to be addressed for applications in nanoelectronic devices.
Tectonic Difference and Genetic Mechanism of Buried Hill in Southern Bohai Area

Wu Qingxun
, Wei Ajuan, Wang Yuechuan, Peng Jingsong, Xiao Shuguang, Gao Kunshun, Guo Yonghua, Deng Hui

地球科学(中国地质大学学报) , 2018, DOI: 10.3799/dqkx.2018.578
Abstract: 目前,针对渤海南部潜山地层结构、构造演化的研究较少.应用三维地震资料、钻井资料,系统分析了该区潜山断裂类型、地层构造类型、成因演化和动力学背景.研究表明,近南北向郯庐走滑断裂和近东西向反转断裂共同控制了研究区潜山地层分布,进而造成了研究区潜山地层的结构、构造差异.近南北向郯庐走滑断裂为调节东西两侧挤压强度差异的同印支造山期断层.郯庐走滑断裂西支以西挤压变形强度相对较弱,普遍发育古生界薄底或秃底构造,以“中生界+古生界+前寒武系”三层结构为主;以东挤压变形作用则相对较强,表现为强烈隆升,古生界剥蚀殆尽,为“中生界+前寒武系”双层结构,花状走滑构造发育.近东西向反转断层为印支期逆冲断层,燕山期伸展反转,现今断裂上升盘残存古生界,下降盘古生界剥蚀殆尽.横向挤压收缩差异是导致研究区潜山地层结构、构造差异的主要原因.
At present, there barely have studies on the stratigraphic structure and tectonic evolution of the buried hill in southern Bohai Sea area. Combined with the 3D seismic data and well data, this study was carried out on the fault types of the buried hills, the structural styles of the buried hills and the genesis and evolution of the buried hills and dynamic background of the buried hills. The results show that the Tanlu strike-slip faults trending near SN direction and the extension faults trending near EW direction jointly controlled the stratigraphic distribution of the buried hill strata, thus affecting the structural differences of the buried hill strata. The Tanlu strike-slip fault trending near SN direction was transform fault in Indo-Chinese epoch, which regulated the compressive strength of the both sides of east and west. The compressive deformation is relatively weak on the west side of the west branch of the Tanlu strike-slip fault, which led to the general development of "thin based" or "bald based". Paleozoic structures that are dominatated by three-layer-structures of Mesozoic+Paleozoic+Precambrian. The compressive deformation on the east side of the west branch was relatively strong, which led to the development of strong uplift, where the Paleozoic stratum has been completely eroded and two-layer-structures of Mesozoic+Precambrian dominate. The reverse faults trending near EW direction were thrust faults in Indo-Chinese epoch, and developed extension and inversion in late Yanshan epoch, in which Paleozoic still remains in upthrow side of the fault but almost completely eroded in downthrow side of the fault. The diversity of the amount of lateral extrusion shrinkage was the main cause for the difference of structural styles of the buried hills in the study area
On the road: Clinical trials with stem cell extended to non-hematologic disease  [PDF]
Jinyang Yu, Yanqiu Yu
Advances in Bioscience and Biotechnology (ABB) , 2013, DOI: 10.4236/abb.2013.42031
Increasing evidence in scientific journals declares that stem cell can be used in human medicine for therapeutic purposes. We reviewed the lated literature on clinical trials conducted with stem cells. The main information was offered by
http://www.ClinicalTrials.gov. These clinical trials cover almost all human diseases, from hematologic diseases to non-hematologic diseases including Interventional trials and observational trials. In conclusion, at present, the clinical trials with stem cells have been extending to almost all human diseases. Optimal medicinal effect reported in some non-hematologic diseases is pushing the advance of stem cells therapy
Comparison of the Water Quality between the Surface Microlayer and Subsurface Water in Typical Water Bodies in Sichuan  [PDF]
Jiang Yu
Journal of Water Resource and Protection (JWARP) , 2010, DOI: 10.4236/jwarp.2010.210101
Abstract: Investigation and assessment of water quality status in the surface microlayer (SML) and subsurface water (SSW) in several kinds of typical water bodies in Sichuan were carried out from May to June 2010.The results showed that N, P were enriched to some extent at SML in Xichi pool, Funan River and Longquan reservoir, which made concentrations of the indexes such as total nitrogen (TN), total phosphorus (TP), chemical oxygen demand (COD)of SML be much higher than those of SSW (P<0.05), and the exceeding rates were up to 100%. The contents of TN,TP,COD of SML and SSW in Xichi pool, and Funan River exceeded III even Ⅳlevel of water quality standard, while these indexes in Longquan reservoir were lower than Ⅲ or Ⅱlevel of water quality standard. Though Chl. a mass concentration at SML and SSW in Funan River was prominently lower than those in Xichi pool and Longquan reservoir, according to the eutrophic evaluation standard, the water bodies of SML and SSW in Funan River and Xichi pool were in middle eutrophication, the highest index of eutrophication (E value) was up to 66.78, while there was light entuophic in Longquan reservoir, and there had obvious difference with E value and COD, TP, TN (P<0.05). This research shows that the water quality of Longquan reservoir is generally well. While Funan River is a middle eutrophication, and its pollution is more serious than Xichi pool, the two waters belong to national III even IV level, and SML has the capability of enrichment to the pollutants such as N, P.
Career Success of Knowledge workers: The Effects of Perceived Organizational Support and Person-Job Fit  [PDF]
Yu Chen
iBusiness (IB) , 2010, DOI: 10.4236/ib.2010.24051
Abstract: The purpose of this paper is to review relevant literatures on career success and develop a theoretical framework and testable propositions concerning how person-job ?t and perceived organizational support relate to career success.
An oversampling system for ECG acquisition  [PDF]
Yu Zhou
Journal of Biomedical Science and Engineering (JBiSE) , 2009, DOI: 10.4236/jbise.2009.27075
Abstract: Traditional ECG acquisition system lacks for flexibility. To improve the flexibility of ECG acquisition system and the signal-to-noise ratio of ECG, a new ECG acquisition system was designed based on DAQ card and Labview and oversampling was implemented in Labview. And analog signal conditioning circuit was improved on. The result indicated that the system could detect ECG signal accurately with high signal-to-noise ratio and the signal processing methods could be adjusted easily. So the new system can satisfy many kinds of ECG acquisition. It is a flexible experiment platform for exploring new ECG acquisition methods.
A Study on the Career Commitment Factor Structure of Knowledge Staff  [PDF]
iBusiness (IB) , 2009, DOI: 10.4236/ib.2009.11004
Abstract: This paper studied the knowledge staff’s career commitment factor structure. The datas from 123 knowledge employees were examined by factor analysis, descriptive analysis and so on. The results showed: a)The career commitment of knowledge staff consists of four dimensions: affective commitment, continuance commitment, career resilience and career loyalty. b)All the reliability and validity indexes of the modified questionnaire are satisfactory.
Moved Score Confidence Intervals for Means of Discrete Distributions  [PDF]
Yu Guan
Open Journal of Statistics (OJS) , 2011, DOI: 10.4236/ojs.2011.12009
Abstract: Let X denote a discrete distribution as Poisson, binomial or negative binomial variable. The score confidence interval for the mean of X is obtained based on inverting the hypothesis test and the central limit theorem is discussed and recommended widely. But it has sharp downward spikes for small means. This paper proposes to move the score interval left a little (about 0.04 unit), called by moved score confidence interval. Numerical computation and Edgeworth expansion show that the moved score interval is analogous to the score interval completely and behaves better for moderate means; for small means the moved interval raises the infimum of the coverage probability and improves the sharp spikes significantly. Especially, it has unified explicit formulations to compute easily.
Page 1 /61052
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.