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Bifurcations of limit Cycles in A Perturbed Quintic Hamiltonian System with Six Double Homoclinic Loops

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Acta Mathematicae Applicatae Sinica 2008年第2期24卷 313-328页

作者： Yong-xi Gao yu-hai Wu li-xin Tian Department of Mathematics Jiang Su University Zhenjiang 212013 China

This paper concerns with the number and distributions of limit cycles of a quintic subject to a seven-degree perturbation. With the aid of numeric integral computation provided by Mathematica 4.1, at least 45 limit cycles are found in the above system by applying the method of double homoclinic loops bifurcation, Hopf bifurcation and qualitative analysis. The four configurations of 45 limit cycles of the system are also shown. The results obtained are useful to the study of the weakened 16th Hilbert Problem.

关键词： limit cycles the Hilbert's 16th problem the double homoclinic loops stability Poincare-Bendixsontheorem

Thermal Expansion Behavior of Amorphous Fe-Si-B Alloys

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Journal of Iron and Steel Research International 2011年第6期18卷 74-78页

作者： SU Chao NIU yu chao li hai feng HUANG Guo wei WANG Xian-zhong School of Materials Science and Engineering Shandong Jianzhu University Jinan 250101 Shandong China

To study the thermal expansion of amorphous Fe-Si-B alloys, the amorphous Fe1.8Si9B1.3 and Fe73.5Nb3-CU1Si13.5B3 and their crystallized alloys were detected using thermal dilatometer. The results indicate that at the same temperature, the relative length change （ΔL/L0） values of the two Fe-based amorphous alloys decrease with increasing heating rate, but those of their crystallized alloys show an opposite trend. It is concluded that the effect of heating rate on the ΔL/L0 of amorphous and crystallized alloys is related to free volume and defects, respectively.

关键词： amorphous alloy thermal expansion heating rate free volume defect

Spatial Interpolation and Sample Size Optimization for Soil Copper(Cu) Investigation in Cropland Soil at County Scale Using Cokriging

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Agricultural Sciences in China 2009年第11期8卷 1369-1377页

作者： PANG Su,li Ting-xuan,WANG Yong-dong,yu hai-ying and li Xi College of Resource and Environmental Science,Sichuan Agricultural University,Ya’an 625014,P.R.China College of Resource and Environmental Science Sichuan Agricultural University Ya'an 625014 P.R. China

Knowledge on spatial distribution and sampling size optimization of soil copper （Cu） could lay solid foundations for environmetal quality survey of agricultural soils at county scale. In this investigation, cokriging method was used to conduct the interpolation of Cu concentraiton in cropland soil in Shuangliu County, Sichuan Province, China. Based on the original 623 physicochmically measured soil samples, 560, 498, and 432 sub-samples were randomly selected as target variable and soil organic matter （SOM） of the whole original samples as auxiliary variable. Interpolation results using Cokriging under different sampling numbers were evaluated for their applicability in estimating the spatial distribution of soil Cu at county sacle. The results showed that the root mean square error （RMSE） produced by Cokriging decreased from 0.9 to 7.77%, correlation coefficient between the predicted values and the measured increased from 1.76 to 9.76% in comparison with the ordinary Kriging under the corresponding sample sizes. The prediction accuracy using Cokriging was still higher than original 623 data using ordinary Kriging even as sample size reduced 10%, and their interpolation maps were highly in agreement. Therefore, Cokriging was proven to be a more accurate and economic method which could provide more information and benefit for the studies on spatial distribution of soil pollutants at county scale.

关键词： cropland soil county scale copper Cokriging sampling size

Effects of mixture of lidocaine and ropivacaine at different concentrations on the central nervous system and cardiovascular toxicity in rats

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Chinese Medical Journal 2010年第1期123卷 79-83页

作者： WAN Qiu-xia BO yu-long li hai-bo li Wen-zhi Department of Anesthesiology Second Affiliated Hospital ofHarbin Medical University Harbin Heilongjiang 150086 China

Background lidocaine and ropivacaine are often combined in clinical practice to obtain a rapid onset and a prolonged duration of action. However, the systemic toxicity of their mixture at different concentrations is unclear. This study aimed to compare the systemic toxicity of the mixture of ropivacaine and lidocaine at different concentrations when administered intravenously in rats. Methods Forty-eJght male WJstar rats were randomly divided into 4 groups （n=12 each）： 0.5% ropJvacaine （group Ⅰ）; 1.0% ropivacaine and 1.0% lidocaine mixture （group Ⅱ）; 1.0% ropivacaine and 2.0% lidocaine mixture （group Ⅲ）; and 1.0% lidocaine （group Ⅳ）. Local anesthetics were infused at a constant rate until cardiac arrest. Electrocardiogram, electroencephalogram and arterial blood pressure were continuously monitored. The onset of toxic manifestations （seizure, dysrhythmia, and cardiac arrest） was recorded, and then the doses of local anesthetics were calculated. Arterial blood samples were drawn for the determination of local anesthetics concentrations by high-performance liquid chromatography. Results The onset of dysrhythmia was later significantly in group IV than in group Ⅰ, group Ⅱ, and group Ⅲ （P 〈0.01）, but there was no significant difference in these groups （P 〉0.05）. The onset of seizure, cardiac arrest in group Ⅰ （（9.2±1.0） min, （37.0±3.0） min） was similar to that in group Ⅱ（（9.1±0.9） min, （35.0±4.0） min）（P 〉0.05）, but both were later in group Ⅲ （（7.5±0.7） min, （28.0±3.0） min）（P 〈0.05）. The onset of each toxic manifestation was significantly later in group Ⅳ than in group Ⅰ （P 〈0.01）. The plasma concentrations of the lidocaine-alone group at the onset of dysrhythmia （DYS）, cardiac arrest （CA）（（41.2±6.8） min, （59.0±9.0） min） were higher than those of the ropivacaine alone group （（20.5±3.8） min, （38.0±8.0） min）（P 〈0.05）. The plasma concentrations of ropivacaine inducing toxic manifestation were not significantly different among groups Ⅰ, Ⅱ, and Ⅲ（P 〉0.05）. Conclusions The

关键词： ropivacaine lidocaine concentration of local anesthetic local anesthetic toxicity

Differentiation of neuromyelitis optica from multiple sclerosis in a cohort from the mainland of China

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Chinese Medical Journal 2014年第18期127卷 3213-3218页

作者： liu Ying ZhaoGuixian yu hai Lyu Chuanzhen li Zhenxin Wu Zhiying Department of Neurology and Institute of Neurology Huashan Hospital Shanghai Medical College Fudan University Shanghai 200040 China

Background Although there were criteria for diagnosis of neuromyelitis optica （NMO） and multiple sclerosis （MS）,it is still difficult to differentiate NMO from MS,due to the overlapping clinical *** it is necessary to characterize clinical features of NMO and MS patients in the mainland of China,to simplify the process of disease diagnosis,and to identify criteria for the differential diagnosis of NMO and *** A total of 138 Chinese Han patients from the mainland of China including 73 NMO,60 MS and 5 MS-like patients with positive NMO-IgG were included in the *** records were reviewed retrospectively and the results of clinical examination,laboratory experiments,magnetic resonance imaging （MRI） and evoked potentials （EPs） were compared between NMO and MS *** addition,the relationship between the NMO-IgG serologic status and clinical characteristics were *** Compared with MS patients （1.3∶ 1.0）,more female prevalence was observed in NMO patients （4.2∶ 1.0; P=0.003）.There were also statistically significant differences in visual EPs,oligoclonal bands,brainstem lesions in MRI and longitudinally extensive spinal cord lesions （LESCLs） between NMO and MS *** lesions observed in brain MRI were found in 17.9% of MS patients,over 3.7 times higher than in NMO patients （4.8%,P=0.024）.When stratified NMO patients by NMO-IgG,LESCLs were found in 42.1% of NMO-IgG-negative NMO patients,over 3.5 times higher than in NMO-IgG-positive patients （11.9%,P=0.008）.Statistical difference was also observed in CD4＋/CD8＋ ratios between NMO-IgG-positive and-negative NMO *** Comprehensive analysis of MRI,laboratory and EPs data can facilitate differential diagnosis of MS and *** addition,the combination of LESCLs and brain MRI findings failing to satisfy MRI criteria for MS is highly sensitive and specific for NMO.

关键词： neuromyelitis optica multiple sclerosis Chinese

A DFT study on the reaction mechanisms of alkene dehydrogenative silylation catalayzed by bis(imino) pyridine cobalt complex

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A DFT study on the reaction mechanisms of alkene dehydrogena...

Design and Implementation of an Ultrasonic Heat Meter Based on MSP430F437

第十三届全国量子化学会议

作者： Dandan Yang hai-yu li Cai-Hong Guo hai-Shun Wu School of Chemical and Material Science Shanxi Normal UniversityKey Laboratory of Magnetic Molecules&Magnetic Information Materials Ministry of Education

An in-depth theoretical study has been performed to investigate the mechanism of dehydrogenative silylation catalyzed by the aryl-substituted bis（imino）pyridine cobalt（ Ⅰ） methyl complex,(PDI)CoPH(PDI=2,6-（2,4,6-MeCH-N=CMe）CH N). It reveals that the true active species is an cobalt silyl complex. The catalytic free energy profiles of sterically varied terminal alkenes with tertiary silanes show a pronounced ligand-dependent regioselectivity. Our calculations explain why the allylsilane is the exclusive produc t for relatively small α-olefins, while a small amount of vinysilane is co-product for relatively large α-olefins very well. The steric factor plays a crucial role in the regioselectivit y for the dehydrogenative silylation of al kene via bis（imino）pyridine cobalt complex. These results are in good agreement with the experimental observations and provide insights into the design of new catalysts for the regioselectively dehydrogenative silylation reactions.

关键词： bis(imino)pyridine cobalt complex dehydrogenative silylation allylsilane regioselectivity

来源： cnki会议评论

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Computer Aided Drafting,Design and Manufacturing 2011年第2期21卷 32-39页

作者： li yue HE yu-zhu ZHOU hai-li CHEN Gong ZHANG Qingrong School of Instrumentation Science and Opto-Elctronics Engineering Beijing University of Aeronautics and Astronautic Beijing 100191 China

Flowing with the reform of the hot water heating method in China, heat meter will enter into households in the near future. A portable ultrasonic heat meter is designed in this paper. The meter uses chip microprocessor MSP430F437 as the data process core, and uses ultrasonic flow sensor to measure flow rate of the hot water, and capture input and output temperatures of the hot water using the thermal resistance sensor Ptl000, and then household energy consumption is calculated via temperature difference between input temperature and output temperature of the hot water multiplied by volume of hot water that is calculated though flow rate integration of hot water. In order to test the performance of the proposed heat meter, experiments is carried out. Both the temperature and flow measurement results satisfy the requirements of accuracy and the heat meter is effective in the heat measurement.

关键词： heat meter MSP430F437 ultrasonic flow sensor thermal resistance sensor

一种油田污水处理新方法——悬浮污泥过滤污水净化处理技术

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自然灾害学报 2005年第1期14卷 161-164页

作者：于海力中国地震局工程力学研究所黑龙江哈尔滨150080

随着人们环境保护意识的逐渐加强,油田采油过程中产生的大量含油污水的处理问题越来越受到人们的重视。做好这部分污水的处理,不仅可以保护好环境,而且还可以将处理后的污水回注油层,节约大量的水资源。为此,介绍一种油田污水处理的新... 详细信息

随着人们环境保护意识的逐渐加强,油田采油过程中产生的大量含油污水的处理问题越来越受到人们的重视。做好这部分污水的处理,不仅可以保护好环境,而且还可以将处理后的污水回注油层,节约大量的水资源。为此,介绍一种油田污水处理的新技术———SSF(悬浮污泥过滤 )污水净化处理技术。

关键词：油田污水净化处理

^(99m)Tc-AMD3100:A novel potential receptor-targeting radiopharmaceutical for tumor imaging

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Chinese Chemical Letters 2010年第4期21卷 461-463页

作者： Jin Ming Zhang~(a,),Jia He Tian~a,Tian Ran li~a, hai yu Guo~a,li Shen~b a Department of Nuclear Medicine,The PLA General Hospital,Beijing,100853,China b Peking University Health Science Center,Beijing,100191,China Department of Nuclear Medicine The PLA General Hospital Beijing 100853 China Peking University Health Science Center Beijing 100191 China

The chemokine CXCR4 receptor is over-expressed in a wide variety of *** this study,AMD3100,which was a prototype non-peptide antagonist of CXCR4 receptor,was labeled with;Tc.;Tc-AMD3100 was verified by thin layer radio chromatography（TLRC）.The tumor-localizing properties of;Tc-AMD3100 were evaluated and proved in mice bearing Hep-G2 tumor xenograft.;Tc-AMD3100 was a promising,novel receptor-specific radiopharmaceutical with potential application in the imaging of human tumors.

关键词： ^(99m)Tc Chemokine CXCR4 AMD3100 Tumor imaging