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Chinese Chemical Letters 2006年第2期17卷 231-234页

作者： Yue ling WANG Zhong Bo HU zhuo Bin YUAN Department of Chemistry Graduate School of the Chinese Academy of Sciences Beijing 100049

Ionic liquid （1-ethyl-3-methylimidazolium tetrafluoroborate, 1E-3MI-TFB） and HP-β- CD as modifier was added to the buffer to separate hyperoside, luteolin and chlorogenic acid. Experiments explored the effect of concentration of 1E-3MI-TFB and HP-β-CD on separation. The results indicated that 1.0 mmol/L HP-β-CD and 1%0 （v/v） 1E-3MI-TFB added to the buffer simultaneously could achieve a good compromise of resolution and analysis time. Capillary experiments and UV spectra indicated that there was interaction between 1E-3MI-TFB and analytes.

关键词： Ionic liquid 1-ethyl-3-methylimidazolium tetrafluorobomte capillary zone electrophoresis lute.olin hyperoside chlorogenic acid.

Heat Flow Distribution and Thermal Mechanism Analysis of the Gonghe Basin based on Gravity and Magnetic Methods

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Acta Geologica Sinica(English Edition) 2021年第6期95卷 1892-1901页

作者： WANG zhuo ZENG Zhaofa LIU zhuo ZHAO Xueyu LI Jing BAI Lige ZHANG ling College of Geo-Exploration Science and Technology Jilin UniversityChangchun 130026China School of Biological Earth and Environmental SciencesUniversity of New South WalesKensingtonNSW 2052Australia

Geothermal resource is indispensable as a clean, renewable, stable and cheap resource. Nowadays in China, the Gonghe Basin, located in northeastern Qinghai Province, has been thought to be a promising geothermal area. To explore geothermal energy potential in and around the Gonghe Basin, geophysical means including magnetic and gravity methods were used to plot distribution. Firstly, we inversed Moho depth and Curie point depth in and around the basin using gravity and magnetic data, respectively, through an improved Parker–Oldenburg algorithm. Secondly, seven different thermal models were established, considering radiogenic heat, basement depth, anomalous heat source and simulated corresponding temperature field and heat flow. These were analyzed numerically and we found the high heat flow in the Gonghe Basin coacted with radiogenic heat, an anomalous heat source and conductive heat. The distribution of seismic activities indicates that the Langshan–Wuwei–Gonghe Fault might have provided channels for transporting heat effectively.

关键词： geothermal energy heat flow thermal mechanism Curie point depth Moho Depth Gonghe Qinghai–Tibet Plateau

The north-south asymmetry of solar filaments separately at low and high latitudes in solar cycle 23

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Research in Astronomy and Astrophysics 2015年第1期15卷 77-84页

作者： De-Fang kong Zhi-Ning Qu Qiao-ling Guo Yunnan Observatories Chinese Academy of Sciences University of Chinese Academy of Sciences Key Laboratory of Solar Activity National Astronomical Observatories Chinese Academy of Sciences College of Mathematics Physics and Information Engineering Jiaxing University

We present the results of a study on the north-south asymmetry of solar filaments at low（〈50°） and high（〉60°） latitudes using daily filament numbers from January 1998 to November 2008（solar cycle 23）. It is found that the northern hemisphere is dominant at low latitudes for cycle 23. However, a similar asymmetry does not occur for solar filaments at high latitudes. The present study indicates that the hemispheric asymmetry of solar filaments at high latitudes in a cycle appears to have little connection with that at low latitudes. Our results support that the observed magnetic fields at high latitudes include two components： one comes from the emergence of the magnetic fields from the solar interior and the other comes from the drift of the magnetic activity at low latitudes.

关键词： Sun: activity Sun: filaments,prominences methods: data analysis

Steroids from the Roots of Asparagus officinalis and Their Cytotoxic Activity

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Journal of Integrative Plant Biology 2008年第6期50卷 717-722页

作者： Xue-Feng Huang Yu-Ying Lin ling-Yi kong Department of Natural Medicinal Chemistry China Pharmaceutical University Nanjing 210009 China

One new （Sarsasapogenin O） and seven known steroids were isolated from the roots of Asparagus offlcinalis L. Their structures were elucidated on the basis of spectroscopic analysis, including various 2D-NMR techniques, hydrolysis, and by comparison of spectral data of known compounds. These compounds together with nine steroids which were previously isolated from this plant, were tested for cytotoxic activity. Among them, eight compounds displayed significant cytotoxiciUes against human A2780, HO-8910, Eca-109, MGC-803, CNE, LTEP-a-2, KB and mouse L1210 tumor cells.

关键词： Asparagus officinalis cytotoxic activity Sarsasapogenin O steroid

The deformation and permeability of Yanji mudstone under cyclic loading and unloading

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Journal of Mountain Science 2019年第12期16卷 2907-2919页

作者： ZENG Zhi-xiong kong ling-wei WANG Jun-tao State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan 430071China University of Chinese Academy of Sciences Beijing 100049China Ecole des Ponts ParisTech U.R.Navier/CERMES6 et 8 av.Blaise PascalCite DescartesChamps-sur-Mame77455 Mame-la-Vallee cedex 2France

During the constructions of motorways and high-speed railway lines in the Yanji Basin,large amounts of excess mudstones due to the enormous tunnel excavations and slope cuts would be deposited as *** the deformation and permeability of Yanji mudstone became important for the design,construction and operation of the *** paper presents an experimental study on the deformation and permeability of Yanji mudstone by carrying out a series of oedometer tests with loading/unloading *** results show that the sample with a lower initial water content exhibited greater swelling deformation after inundation,a lower yield stress,greater deformation and a higher hydraulic conductivity during the loading/unloading *** the number of loading/unloading cycles increased,the yield stress and accumulated plastic deformation increased,while the compression index,rebound index and hydraulic conductivity *** samples became stiffer and their hydromechanical behaviour tended to be stable after three *** compression curves could be divided into pre-yield and post-yield *** post-yield zones of compression curves and the rebound curves could be normalized into a unique line,and the pre-yield zones of the compression curves could be described as *** equations were developed to predict mudstone deformation under cyclic loading and ***,an empirical relationship between the hydraulic conductivity and void ratio was also *** ability of the proposed methods was verified by the overall good agreement between the experimental results and predicted values.

关键词： Mudstone Swelling Cyclic loading and unloading Deformation Permeability

Pathological differential diagnosis of solid-pseudopapillary neoplasm and endocrine tumors of the pancreas

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World Journal of Gastroenterology 2010年第8期16卷 1025-1030页

作者： Liu, Bao-An Li, zhuo-Ming Su, Zhan-San She, Xiao-ling Cent S Univ Xiangya Basic Med Sch Dept Pathol Changsha 410013 Hunan Peoples R China Cent S Univ Xiangya Hosp 3 Dept Pathol Changsha 410013 Hunan Peoples R China Cent S Univ Xiangya Hosp 2 Dept Pathol Changsha 410006 Hunan Peoples R China

AIM:To investigate differential points of solid-pseudo-papillary neoplasm (SPN) of the pancreas and pancre-atic endocrine tumor (PET).METHODS:Ten cases of SPN and fourteen cases of PET were studied in this retrospective study. Clinical and pathologic features,immunostaining reactions and β-catenin gene mutations were ***:The mean age of SPN patients was 25.6 years and these patients had no specific symptoms. The mean diameter of the tumors was 11.0 cm,9/10 cases were cystic or a mixture of solid and cystic structures,and there was hemorrhage and necrosis on the cut surface in 8/10 (80%) cases. Characteristic pseudo-papillary structure and discohesive appearance of the neoplastic cells were observed in all 10 (100%) cases. The results of immunostaining showed that nuclear expression of β-catenin and loss of E-cadherin in all the cases,was only seen in SPN. Molecular studies discov-ered that 9/10 (90%) cases harbored a point mutation of exon 3 in β-catenin gene. On the other hand,the mean age of PET patients was 43.1 years. Eight of 14 cases presented with symptoms caused by hypoglyce-mia,and the other 6 cases presented with symptoms similar to those of SPN. The mean size of the tumors was 2.9 cm,most of the tumors were solid,only 3/14 (21%) were a mixture of solid and cystic structures,and macroscopic hemorrhage and necrosis were much less common (3/14,21%). Histologically,tumor cells were arranged in trabecular,acinar or solid patterns and demonstrated no pseudopapillary structure and discohesive appearance in all 14 (100%) cases. The results of immunostaining and mutation detection were completely different with SPN that membrane and cytoplastic expression of β-catenin without loss of E-cadherin,as well as no mutation in β-catenin gene in all the cases. CONCLUSION:Both macroscopic and microscopic features of SPN are quite characteristic. It is not difficult to distinguish it from PET. If necessary,immunos-taining of β-catenin and E-cadherin is quite he

关键词： Solid-pseudopapillary neoplasm of the pan-creas Pancreatic endocrine tumor Immunohistochem-istry β-catenin gene Differential diagnosis

Harmonic Energy Transfer for Extreme Waves in Current

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China Ocean Engineering 2017年第2期31卷 160-166页

作者： NING De-zhi DU Jun zhuo Xiao-ling LIU Jia-zhen TENG Bin State Kay Laboratory of Coastal and Offshore Engineering Dalian University of Technology

Ning et al. （2015） developed a 2D fully nonlinear potential model to investigate the interaction between focused waves and uniform currents. The effects of uniform current on focusing wave crest, focal time and focal position were given. As its extension, harmonic energy transfer for focused waves in uniform current is studied using the proposed model by Ning et al. （2015） and Fast Fourier Transformation （FFT） technique in this study. It shows that the strong opposing currents, inducing partial wave blocking and reducing the extreme wave crest, make the nonlinear energy transfer non-reversible in the focusing and defocusing processes. The numerical results also provide an explanation to address the shifts of focal points in consideration of the combination effects of wave nonlinearity and current.

关键词： extreme wave focused wave group wave-current interaction fully nonlinear partial wave-blocking

Robust lossless data hiding scheme

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Journal of Zhejiang University-Science C(Computers and Electronics) 2010年第2期11卷 101-110页

作者： Xian-ting ZENG Xue-zeng PAN ling-di PING zhuo LI School of Computer Science and Technology Zhejiang University Hangzhou 310027 China College of Information Engineering China Jiliang University Hangzhou 310018 China

This paper presents a robust lossless data hiding scheme. The original cover image can be recovered without any distortion after data extraction if the stego-image remains intact, and conversely, the hidden data can still be extracted correctly if the stego-image goes through JPEG compression to some extent. A cover image is divided into a number of non-overlapping blocks, and the arithmetic difference of each block is calculated. By shifting the arithmetic difference value, we can embed bits into the blocks. The shift quantity and shifting rule are fixed for all blocks, and reversibility is achieved. Furthermore, because the bit-0- and bit-1-zones are separated and the particularity of the arithmetic differences, minor changes applied to the stego-image generated by non-malicious attacks such as JPEG compression will not cause the bit-0- and bit-l-zones to overlap, and robustness is achieved. The new embedding mechanism can enhance embedding capacity and the addition of a threshold can make the al- gorithm more robust. Experimental results showed that, compared with previous schemes, the performance of the proposed scheme is significantly improved.

关键词： Watermarking Lossless data hiding Reversible data hiding Robust lossless data hiding Semi-fragile authentication

NONLINEAR DYNAMICAL ANALYSIS OF BIFURCATION AND CONFLUENCE OF THE PACIFIC WESTERN BOUNDARY CURRENTS

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Journal of Hydrodynamics 2012年第3期24卷 383-390页

作者： NI Guo-xi JIANG Song JU Qiang-chang kong ling-hai LCP Institute of Applied Physics and Computational Mathematics Beijing 100088 China

In this paper, we analyze the bifurcation and the confluence of the Pacific western boundary currents by an analytical approach. Applying the conservation law, the geostrophic balance relation and the Bernoulli integral to a reduced gravity model, we get a quantitative relation for the outflow and the inflow, and establish the related formulae for the width and the veering angle of offshore currents under the inflow condition. Furthermore, a comparison between the volume transport based on the observation data and the analytical value for the Pacific western boundary currents is presented, which validates the theoretical analysis.

关键词： Pacific western boundary currents bifurcation confluence volume transport reduced gravity model

Decyloxyphenyl-substituted Quinoxaline-embedded Conjugated Electrochromic Polymers with High Switching Stability and Fast Response Speed

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Chinese Journal of Polymer Science 2016年第4期34卷 407-419页

作者： Zhen Xu ling-qian kong 赵金生范维玉 State Key Laboratory of Heavy Oil Processing China Universtty of Petroleum(East China)Qingdao 266555China Dongchang College Liaocheng UniversityLiaocheng 252059China Shandong Key Laboratory of Chemical Energy Storage and Novel Cell Technology Liaocheng UniversityLiaocheng 252059China

Two novel decyloxyphenylquinoxaline-based donor-acceptor （D-A） electroactive monomers bearing dialkoxythiophene as the donor unit are synthesized using Stille coupling reaction. The corresponding polymers, poly[2,3- bis（4-decyloxyphenyl）-5,8-bis（3,4-dimethoxylthiophen-2-yl）quinoxaline] （P1） and poly[2,3-bis（4-decyloxyphenyl）-5,8- bis（2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl）quinoxaline] （P2）, are directly deposited onto the working electrode surface by electropolymerization. All materials were characterized by nuclear magnetic resonance （NMR）, mass spectrometry （MS）, scanning electron microscopy （SEM）, cyclic voltammetry （CV）, ultraviolet-visible absorption spectrometry （UV-Vis） and spectro-electrochemical measurements. Electrochemical studies demonstrate that both polymers are capable of showing both reasonable n- and p-doping processes, and advanced long-term switching stabilities. 3,4-Ethylenedioxythiophene substituted for 3,4-dimethoxythiophene as a donor unit, which enhances the conjugated double-bond character of the conducting polymer, thus leading to a lower electronic band-gap. Likewise, the neutral state color of the synthesized polymer tuned from blue to blue-green corresponding to the red shift of the maximum absorption wavelengths in the visible region. In addition, kinetics study of P1 revealed 42% （595 nm）, 30% （839 nm） and 69% （1500 nm） transmittance changes （A7%）, while P2 exhibited 32% （740 nm）, 71% （2000 nm） at the dominant wavelengths. It was also observed that both films could switch quickly between the neutral state and oxidation state, with the response time less than 1 s both in visible and near infrared regions.

关键词： 3,4-Dimethoxythiophene Decyloxyphenylquinoxaline High switching stability Fast response time.