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Acta Mathematicae Applicatae Sinica 2017年第1期33卷 1-24页

作者： Shao-wei LI Wei-guo ZHANG Van ZHAO Zheng-ming LI Xiang LI Business School University of Shanghai for Science and Technology Shanghai 200093 China School of Mathematics and Information Engineering Taizhou University Taizhou 317000 China College of Science University of Shanghai for Science and Technology Shanghai 200093 China

This paper makes qualitative analysis to the bounded traveling wave solutions for a kind of nonlinear dispersive-dissipative equation, and considers its solving problem. The relation is investigated between behavior of its solution and the dissipation coefficient. Further, all approximate damped oscillatory solutions when dissipation coefficient is small are presented by utilizing the method of undetermined coefficients according to the theory of rotated vector field in planar dynamical systems. Finally, error estimate is given by establishing the integral equation which reflects the relation between approximate and exact damped oscillatory solutions applying the idea of homogenization principle.

关键词： nonlinear dispersive-dissipative equation qualitative analysis solitary wave solution dampedoscillatory solution error estimate

qualitative analysis of aromatic compounds via 1D TOCSY techniques

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Magnetic Resonance Letters 2024年第1期4卷 21-27页

作者： Wenbo Dong Qi Zhao Jiancheng Zhao Jiarong Zhang Yingxiong Wang Yan Qiao State Key Laboratory of Coal Conversion Institute of Coal ChemistryChinese Academy of Sciences27 South Taoyuan RoadTaiyuan030001China Graduate University of Chinese Academy of Sciences Beijing100049China Marine Biomedical Research Institution Guangdong Medical UniversityZhanjiang524023China College of Chemistry Taiyuan University of Technology79 Yingze West StreetWanbailin DistrictTaiyuan030024China

The aromatic compounds,including o-xylene,m-xylene,p-xylene,and ethylbenzene,primarily originate from the catalytic reforming of crude oil,and have a wide variety of applications.However,because of similar physical and chemical properties,these compounds are difficult to be identified by gas chromatography(GC)without standard samples.With the development of modern nuclear magnetic resonance(NMR)techniques,NMR has emerged as a powerful and efficient tool for the rapid analysis of complex and crude mixtures without purification.In this study,the parameters of one-dimensional(1D)total correlation spectroscopy(TOCSY)NMR techniques,including 1D selective gradient TOCSY and 1D chemicalshift-selective filtration(CSSF)with TOCSY,were optimized to obtain comprehensive molecular structure information.The results indicate that the overlapped signals in NMR spectra of nonpolar aromatic compounds(including o-xylene,m-xylene,p-xylene and ethylbenzene),polar aromatic compounds(benzyl alcohol,benzaldehyde,benzoic acid),and aromatic compounds with additional conjugated bonds(styrene)can be resolved in 1D TOCSY.More importantly,full molecular structures can be clearly distinguished by setting appropriate mixing time in 1D TOCSY.This approach simplifies the NMR spectra,provides structural information of entire molecules,and can be applied for the analysis of other structural isomers.

关键词： 1D TOCSY NMR technologies Xylenes Aromatic compounds Structure information of entire molecular qualitative analysis

qualitative analysis and Solutions of Bounded Traveling Wave for B-BBM Equation

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Acta Mathematicae Applicatae Sinica 2010年第3期26卷 415-426页

作者： Yan Zhao Wei-guo Zhang School of Science University of Shanghai for Science and Technology Shanghai 200093 China

In this paper, we apply the theory of planar dynamical systems to carry out qualitative analysis for the dynamical system corresponding to B-BBM equation, and obtain global phase portraits under various parameter conditions. Then, the relations between the behaviors of bounded traveling wave solutions and the dissipation coeffiicient μ are investigated. We find that a bounded traveling wave solution appears as a kink profile solitary wave solution when μ is more than the critical value obtained in this paper, while a bounded traveling wave solution appears as a damped oscillatory solution when μ is less than it. Furthermore, we explain the solitary wave solutions obtained in previous literature, and point out their positions in global phase portraits. In the meantime, approximate damped oscillatory solutions are given by means of undetermined coefficients method. Finally, based on integral equations that reflect the relations between the approximate damped oscillatory solutions and the implicit exact damped oscillatory solutions, error estimates for the approximate solutions are presented.

关键词： B-BBM equation qualitative analysis global phase portrait solitary wave solution,damped oscillatory solution

DETERMINING HYDROCARBON PROSPECTIVE ZONE USING THE COMBINATION OF qualitative analysis AND FUZZY LOGIC METHOD

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Journal of Systems Science and Systems Engineering 2017年第4期26卷 463-474页

作者： Hidayah Nurul Hasanah Zen Laila Wahyu Trimartanti Zaenal Abidin Agus Maman Abadi Department of Mathematics Yogyakarta State University Indonesia STTN-BATAN Yogyakarta Indonesia

Hydrocarbon prospective zone is a certain layer in a reservoir which is estimated producing oil. The geologists use the qualitative analysis method to find the prospect layers. The research used five variables modeled by three fuzzy membership functions and eight rules of fuzzy logic. The rules cause insensitiveness in the working system. This study therefore was conducted by modeling each of input variables into different models using 36 rules. It aims to determine the existence of hydrocarbon prospective zone through a qualitative analysis in a reservoir using fuzzy inference system with Mamdani method. The data were taken from well log data in reservoir ＂X＂. There were some steps in doing this study, including fuzzification, inference system, and defuzzification. The result showed 99 prospect layers from 3000 layers in reservoir ＂X＂ with 97.7% of accuracy.

关键词： Well log fuzzy logic prospective zone hydrocarbon qualitative analysis

Appropriate choice of collision-induced dissociation energy for qualitative analysis of notoginsenosides based on liquid chromatography hybrid ion trap time-of-flight mass spectrometry

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Chinese Journal of Natural Medicines 2016年第4期14卷 278-285页

作者： WANG Guang-Ji FU Han-Xu XIAO Jing-Cheng YE Wei RAO Tai SHAO Yu-Hao KANG Dian XIE Lin LIANG Yan Key Lab of Drug Metabolism & Pharmacokinetics State Key Laboratory of Natural Medicines China Pharmaceutical University

Liquid chromatography hybrid ion trap/time-of-flight mass spectrometry possesses both the MS^n ability of ion trap and the excellent resolution of a time-of-flight and has been widely used to identify drug metabolites and determine trace multi-components in natural products. Collision energy, one of the most important factors in acquiring MS^n information, could be set freely in the range of 10%–400%. Herein, notoginsenosides were chosen as model compounds to build a novel methodology for the collision energy optimization. Firstly, the fragmental patterns of the representatives for the authentic standards of protopanaxadiol-type and protopanaxatriol-type notoginsenosides were obtained based on accurate MS^2 and MS^3 measurements via liquid chromatography hybrid ion trap/time-of-flight mass spectrometry. The extracted ion chromatograms of characteristic product ions of notoginsenosides in Panax Notoginseng Extract were produced under a series of collision energies and compared to screen the optimum collision energies values for MS^2 and MS^3. The results demonstrated that the qualitative capability of liquid chromatography hybrid ion trap/time-of-flight mass spectrometry was greatly influenced by collision energies, and 50% of MS^2 collision energy was found to produce the highest collision-induced dissociation efficiency for notoginsenosides. Addtionally, the highest collision-induced dissociation efficiency appeared when the collision energy was set at 75% in the MS^3 stage.

关键词： Collision energy Collision-induced dissociation Notoginsenosides qualitative analysis

qualitative and quantitative analysis ofβ-sitosterol marker in virgin camellia oil and virgin olive oil

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Food Quality and Safety 2023年第4期7卷 579-587页

作者：李阳吴旻谕翟量张辉沈立荣 National Engineering Laboratory of Intelligent Food Technology and Equipment Key Laboratory for Agro-Products Postharvest Handling of Ministry of AgricultureKey Laboratory for Agro-Products Nutritional Evaluation of Ministry of AgricultureZhejiang Key Laboratory for Agro-Food ProcessingFuli Institute of Food ScienceCollege of Biosystems Engineering and Food ScienceZhejiang UniversityHangzhouChina Innovation Center of Yangtze River Delta Zhejiang UniversityJiaxingChina

Camellia oil and olive oil with superior economic value are easily adulterated with other,cheaper oils.It is difficult to identify both oils by traditional methods because of their similar fatty acid profiles.In the present study,a novel method for qualitative and quantitative analysis ofβ-sitosterol using GC/MS and GC/FID was developed to identify camellia oil and olive oil.The method validation ofβ-sitosterol analysis showed good linearity and satisfactory values for recovery,accuracy,precision,and repeatability.The linear regression coefficient(R^(2))of the calibration curve was 0.9985.An acceptable limit of detection(0.36 mg/100 g)and limit of quantification(1.20 mg/100 g)were achieved.The spiked recoveries were 95.0%to 100.3%.The relative standard deviation(RSD)of within-day precision was less than 3.26%,and the RSD of retention times and peak areas for repeatability were within 0.03%and 1.08%,respectively.The contents ofβ-sitosterol in virgin camellia oil and virgin olive oil were in the range of 14.1–30.2 mg/100 g and 94.3–173.2 mg/100 g,respectively,indicating that theβ-sitosterol content in the former is seven times that in the latter,andβ-sitosterol could be a potential marker for the authentication and adulteration detection of both oils.

关键词： β-Sitosterol virgin camellia oil(VCO) virgin olive oil(VOO) qualitative analysis quantitative analysis

qualitative and Quantitative analysis of Alkaloids in Cortex Phellodendri by HPLC-ESI-MS/MS and HPLC-DAD

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Chemical Research in Chinese Universities 2011年第1期27卷 38-44页

作者： ZHU Shuang-lai DOU Sheng-shan LIU Xin-ru LIU Run-hui ZHANG Wei-dong HUANG Hong-lin ZHANG Yi HU Yao-hua WANG Shu-ping School of Pharmacy Second Military Medical University Shanghai 200433 P. R. China School of Pharmacy Jiangxi University of Traditional Chinese Medicine Nanchang 330004 P. R. China School of Pharmacy Shanghai Jiaotong University Shanghai 200240 P. R. China School of Pharmacy Fujian University of Traditional Chinese Medicine Fuzhou 350108 P. R. China School of Pharmacy Chengdu University of Traditional Chinese Medicine Chengdu 610075 P. R. China

A combined method of high performance liquid chromatograph-elecrtrospray-ionization mass spectrometer（HPLC-ESI-MS/MS） coupled with a photodiode array detector（HPLC-DAD） and principal component analysis（PCA） was applied to the qualitative and quantitative analyses of alkaloids in Cortex Phellodendri（CP） samples, and to the differentiation of two species of CP, Cortex Phellodendri Chinensis（CPC） and Cortex Phellodendri Amurensis（CPA）. Twenty-two peaks appeared in the HPLC-MS base peak chromatogram of CP detected by the HPLC-ESI-MS/MS analysis, and the alkaloids were identified according to the MSn data, the known MS fragmentation rules and the literature data. Five alkaloids including berberine, palmatine, jatrorrhizine, phellodendrine and magnoflorine were simultaneously determinated by the HPLC-DAD. Berberine was the primary component in all CP samples, and the contents of berberine and palmatine were exploited to be two critical parameters for effective discrimination between the two species of CP. The average content of berberine in CPC（58.75 mg/g） was higher than that in CPA（9.16 mg/g）, while the content of palmatine was less, only 0.25 mg/g in CPC and 4.19 mg/g in CPA. With the use of PCA, samples datasets were separated successfully into two different clusters corresponding to the two species, and berberine, pahnatine, phellodendrine and magnoflorine contribute most to the above mentioned calssifying . The proposed method oroved to be a useful tool in the aualitv control of Chinese herbal medicines.

关键词： Cortex Phellodendri Alkaloid HPLC-ESI-MS/MS Quantitative analysis qualitative analysis Principal component analysis

农产品流通体系影响农产品价格波动的机理与路径

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REGION qualitative analysis OF PREDATOR-PREY SYSTEMS ON TIME SCALES

贸易经济 2022年第4期

作者：王朝辉陈洁光欧进锋

本文采用规范化实地研究方法，运用质性分析软件对某地农产品批发市场92户嵌入式个案的访谈数据进行分析，较为清晰地阐释了农产品流通体系对农产品价格影响的内在机理及路径。来自实地调查事实证据分析表明，农产品流通体系与农产品价... 详细信息

本文采用规范化实地研究方法，运用质性分析软件对某地农产品批发市场92户嵌入式个案的访谈数据进行分析，较为清晰地阐释了农产品流通体系对农产品价格影响的内在机理及路径。来自实地调查事实证据分析表明，农产品流通体系与农产品价格波动之间具有显著的相关性；且农产品流通体系构成要素通过供求关系、经营成本、心理预期等三个控制因素可以综合影响农产品价格波动及幅度；优化农产品流通体系确实能起到抑制农产品价格过度波动的作用。这说明，短期的农产品生产调控或价格补贴措施对抑制农产品价格过度波动作用有限，建立长效的农产品流通体系内在稳定性以消解体制机制性障碍，比过度偏重生产性调节更重要。

关键词：农产品流通体系价格波动实地调查质性分析　　agricultural product circulation system price fluctuation field study qualitative analysis

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Annals of Differential Equations 2008年第1期24卷 121-126页

作者： Zhu Siming Li Yanhui (Math.and Computed Science Academy of Sun-Yatsen University,Guangzhou 510275) Rong Zhixin (IBM,Guangzhou 510620)

We first investigate some basic properties of dynamic equations on time scales,and propose contained curves to describe the jump direction of the discrete points.Then we perform qualitative analysis regarding the planar predator-prey systems on time scales,thereby obtain two theorems of this system.At last,we emulate application examples to discuss the parameters of the system.

关键词： time-scales predator-prey systems contained curves qualitative analysis

Influence of dissipation on solitary wave solution to generalized Boussinesq equation

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Applied Mathematics and Mechanics(English Edition) 2023年第3期44卷 477-498页

作者： Weiguo ZHANG Siyu HONG Xingqian LING Wenxia LI College of Science University of Shanghai for Science and TechnologyShanghai 200093China

This paper uses the theory of planar dynamic systems and the knowledge of reaction-diffusion equations,and then studies the bounded traveling wave solution of the generalized Boussinesq equation affected by dissipation and the influence of dissipation on solitary waves.The dynamic system corresponding to the traveling wave solution of the equation is qualitatively analyzed in detail.The influence of the dissipation coefficient on the solution behavior of the bounded traveling wave is studied,and the critical values that can describe the magnitude of the dissipation effect are,respectively,found for the two cases of b_30 in the equation.The results show that,when the dissipation effect is significant(i.e.,r is greater than the critical value in a certain situation),the traveling wave solution to the generalized Boussinesq equation appears as a kink-shaped solitary wave solution;when the dissipation effect is small(i.e.,r is smaller than the critical value in a certain situation),the traveling wave solution to the equation appears as the oscillation attenuation solution.By using the hypothesis undetermined method,all possible solitary wave solutions to the equation when there is no dissipation effect(i.e.,r=0)and the partial kink-shaped solitary wave solution when the dissipation effect is significant are obtained;in particular,when the dissipation effect is small,an approximate solution of the oscillation attenuation solution can be achieved.This paper is further based on the idea of the homogenization principles.By establishing an integral equation reflecting the relationship between the approximate solution of the oscillation attenuation solution and the exact solution obtained in the paper,and by investigating the asymptotic behavior of the solution at infinity,the error estimate between the approximate solution of the oscillation attenuation solution and the exact solution is obtained,which is an infinitesimal amount that decays exponentially.The influence of the dissipation coefficient on the ampli

关键词： generalized Boussinesq equation influence of dissipation qualitative analysis solitary wave solution oscillation attenuation solution error estimation