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Chemical Research in Chinese Universities 2011年第1期27卷 34-37页

作者： YU Cai-xia yuan bai-qing YOU Tian-yan State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 P. R. China Graduate School of Chinese Academy of Sciences Beijing 100049 P. R. China

The antidepressant trimipramine（Tri） enantiomers were successfully separated by capillary electrophoresis（CE） coupled with electrochemiluminescence（ECL） detection in aqueous-organic media. A dual cyclodextrin（CD） system combining β-CD and hydroxypropyl-β-cyclodextrin（HP-β-CD） was used as chiral selector. Acetonitrile（ACN） was added to the running buffer to improve the separation efficiency, detection sensitivity and repeatability. The method was also successfully applied to the chiral separation of Tri in spiked human urine sample.

关键词： Capillary electrophoresis Electrochemiluminescence Trimipramine Enantioseparation Organic additive

Quality Analysis of Herbal Medicine Products Prepared from Herba Sarcandrae by Capillary Electrophoresis with Electrochemical Detection

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Chemical Research in Chinese Universities 2008年第2期24卷 148-153页

作者： ZHOU Xiao-guang SUN Jin-ying ZHU De-rong yuan bai-qing YOU Tian-yan State Key Laboratory of Electroanalytical Chemistry Changchun institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 P. R. China Graduate School of the Chinese Academy of Sciences Beijing 100039 P. R. China School of Pharmacy Guangdong Medical College Dongguan 523808 P. R. China

A capillary electrophoresis with electrochemical detection（CE-ED） method was developed for the quality analysis of herbal medicine products prepared from the same herb of Herba Sarcandrae： Fufang Caoshanhu tablets, qingrexiaoyanning capsules, and Xuekang oral liquids. Under the optimal analysis conditions, the low detection limit[l.0×10^-7 mol/L（S/N=3）] and the wide linear range（1.0×10^-7-1.0×10^-4 mol/L） were obtained for quality standard compound of isofraxidin. The precisions of the peak current and the migration time（as RSDs） for the real sample analysis were 2.0%-2.6%, and 1.2%-1.8% for isofraxidin, respectively. The contents of isofraxidin detected were 15.77 μg/tablet, 0.48 mg/capsule, 1.2 mg/ampoule（Jiangxi）, and 0.44 mg/ampoule（Dalian） for Fufang Caoshanhu tablets, qingrexiaoyanning capsules, and Xuekang oral liquids from different manufacturers, respectively. Quality estimate was conducted by comparing the contents of isofraxidin in the herbal medicine products with the demanded values of Chinese pharmacopeia. In addition, based on their own unique CE-ED profiles（namely, CE-ED electropherograms） the Xuekang oral liquids from the different manufacturers could be easily identified.

关键词： Capillary electrophoresis Electrochemical detection Chinese patent medicines Herba Sarcandrae Quality analysis

Determination of Amino Acids by Ru(bpy)_3^(2+) Cathodic Electrochemiluminescence with High Sensitivity

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Chemical Research in Chinese Universities 2010年第3期26卷 376-379页

作者： ZHOU Xiao-guang yuan bai-qing ZHANG Lei LIU Yang HAN Dong-xue YOU Tian-yan Department of Chemistry and Chemical Engineering College of Science Northeast Forestry University Harbin 150040 P. R. China State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changehun 130022 P. R. China College of Chemistry Jilin University Changchun 130021 P. R. China

The unique cathodic electrochemiluminescence（ECL） emission of Ru（bpy）3^2＋（bpy=2,2′-bipyridine） was observed via Nation film at Au electrode[Au/Nafion/Ru（bpy）3^2＋] at about 0.20 V（vs. Ag/AgCl） and applied to the determination of several amino acids without prior derivatization with high sensitivity. The cathodic electrochemiluminescence（ECL） exhibits the detection limits and linear ranges of several amino acids comparable to or better than those of capillary electrophoresis with conventional ECL detection method（at 1.10-1.20 V vs. Ag/AgCl） based on precolumn derivatization. The results suggest that the cathodic ECL is promising for the detection of amino acids in bioanalysis.

关键词： Cathodic electrochemiluminescence Ru(bpy)3^2+ Nation Au electrode

Microphysical Insights into a Tornadic Supercell from Dual-Polarization Radar Observations in Jiangsu, China on 14 May 2021

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Journal of Meteorological Research 2024年第2期38卷 303-320页

作者： Chao yuan Yang bai Pengfei SUN Hua bai Lu XIA China Meteorological Administration Tornado Key Laboratory Foshan 528315 Institute of Atmospheric Environment China Meteorological AdministrationShenyang 110166 Panjin National Climate Observatory Panjin 124010 Yangzhou Meteorological Bureau of Jiangsu Province Yangzhou 225100 Yichun Meteorological Bureau of Heilongjiang Province Yichun 153000

Tornadoes are incredibly powerful and destructive natural events,yet the microphysical characteristics of the parent storm and its effects on tornadogenesis remain *** study analyzed polarization radar data of a tornadic supercell that occurred in Jiangsu Province of China on 14 May 2021,in comparison with another tornadic supercell and two non-tornadic supercells that occurred in the same region in *** two tornadic supercells exhibited lower differential reflectivity(ZDR)in the hook echo region compared with the non-tornadic supercells,indicating smaller median drop sizes.A distinct increase in ZDR from the melting of frozen hydrometeors,observed between2.5-and 4.0-km altitude in the non-tornadic storms,was absent in the tornadic *** non-tornadic supercells also displayed substantially higher specific differential phase(KDP)below the melting level,likely aroused from enhanced melting and *** findings suggest fundamental microphysical contrasts between tornadic and nontornadic ***,tornadic supercells have smaller droplets and may reduce melting in hook ***,greater separation between the ZDR arc and the KDP foot was observed during *** vertical gradient of KDP related to the cooling pool strength of the hook echo,regulating rear-flank downdraft *** the limited number of cases investigated,the findings of this study indicate that monitoring ZDR,KDP,and drop size distribution trends could assist with tornado prediction and warnings.

关键词： tornado polarimetric radar supercell hook echo drop size distribution

Optical system for extremely large spectroscopic survey telescope

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Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 158-174页

作者： Ding-qiang Su Hua bai Xiangyan yuan Xiangqun Cui Key Laboratory of the Ministry of Education School of Astronomy and Space ScienceNanjing UniversityNanjing 210023China Nanjing Institute of Astronomical Optics and Technology(NIAOT) Chinese Academy of SciencesNanjing 210042China University of Chinese Academy of Sciences Nanjing 211135China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 101408China

This article presents research work on a spectroscopic survey *** idea is as follows:for such a telescope,a pure reflecting optical system is designed,which should have an aperture and a field of view(FOV)both as large as possible and excellent image quality,and then a strip lensm(lens-prism)atmospheric dispersion corrector(S-ADC)is added,only for correcting the atmospheric *** the fund limitation and the simplicity of scaling up,some 12-m telescopes are designed as ***,Korsch,and Meinel put forward the four-mirror Nasmyth systems I and II,which are used in this *** of 1.5°,2°,and 2.5°are *** all systems,the image qualities are *** the S-ADC relaxes the optical glass size restriction,this 12-m telescope with a FOV of 2.5°can be magnified in proportion to a 16-m *** etendue(from Frenchétendue)and focal surface will now be the largest in the *** such a telescope,a pure reflecting optical system can also be obtained.A subsequent coudésystem is designed with excellent image quality.

关键词： telescopes spectroscopic survey

Reliable calculations of nuclear binding energies by the Gaussian process of machine learning

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Nuclear Science and Techniques 2024年第6期35卷 130-144页

作者： Zi-Yi yuan Dong bai Zhen Wang Zhong-Zhou Ren School of Physics Science and Engineering Tongji UniversityShanghai 200092China College of Science Hohai UniversityNanjing 211100China Key Laboratory of Advanced Micro-Structure Materials Ministry of EducationShanghai 200092China

Reliable calculations of nuclear binding energies are crucial for advancing the research of nuclear physics. Machine learning provides an innovative approach to exploring complex physical problems. In this study, the nuclear binding energies are modeled directly using a machine-learning method called the Gaussian process. First, the binding energies for 2238 nuclei with Z > 20 and N > 20 are calculated using the Gaussian process in a physically motivated feature space, yielding an average deviation of 0.046 MeV and a standard deviation of 0.066 MeV. The results show the good learning ability of the Gaussian process in the studies of binding energies. Then, the predictive power of the Gaussian process is studied by calculating the binding energies for 108 nuclei newly included in AME2020. The theoretical results are in good agreement with the experimental data, reflecting the good predictive power of the Gaussian process. Moreover, the α-decay energies for 1169 nuclei with 50 ≤ Z ≤ 110 are derived from the theoretical binding energies calculated using the Gaussian process. The average deviation and the standard deviation are, respectively, 0.047 MeV and 0.070 MeV. Noticeably, the calculated α-decay energies for the two new isotopes ^ (204 )Ac(Huang et al. Phys Lett B 834, 137484(2022)) and ^ (207) Th(Yang et al. Phys Rev C 105, L051302(2022)) agree well with the latest experimental data. These results demonstrate that the Gaussian process is reliable for the calculations of nuclear binding energies. Finally, the α-decay properties of some unknown actinide nuclei are predicted using the Gaussian process. The predicted results can be useful guides for future research on binding energies and α-decay properties.

关键词： Nuclear binding energies decay Machine learning Gaussian process

Thermal stability of permafrost under U-shaped crushed rock embankment of the qinghai-Tibet Railway

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Advances in Climate Change Research 2024年第1期15卷 158-169页

作者： Kun-Ming XU Guan-Li JIANG Ji CHEN qing-bai WU State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China Beiluhe Observation Station of Frozen Soil Environment and Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou730000China

The U-shaped crushed rock embankment(UCRE),of which widely utilized in the permafrost regions along the qinghai-Tibet Railway,has the capability to rapidly reduce the ground temperature of the underlying ***,there remains uncertainty regarding the adaptation of UCRE to climate change and its long-term cooling *** study focuses on nine UCRE monitoring sites along the qinghai-Tibet Railway to analyze the dynamic variations of the ground temperature underlying permafrost from 2006 to *** efficiency of UCRE in stabilizing permafrost temperature in different permafrost zones is evaluated by considering the permafrost table,ground temperature,and MAGT,as well as the temperature difference between the top and bottom of the crushed rock layer and the ground temperature variation index(GTVI).The results show that UCRE is suitable for application in extremely unstable warm permafrost regions where the MAGT is higher than-0.5℃.Moreover,UCRE effectively diminishes the disparity in permafrost thermal stability between the sunny and shaded shoulders of the *** short-term and long-term effect of cooling permafrost is experiencing a change related with permafrost ***,in stable cold permafrost regions with MAGT lower than-1.5℃,the long-term cooling effect of UCRE on permafrost seems to gradually di-minishes,but UCRE continues to fulfill the role of stabilizing the underlying permafrost thermal state over the *** results show that UCRE can quickly restore and stabilize the thermal state of permafrost in the early stages of construction,and adapt to the influence of future climate *** findings provide important guidance for understanding the variations of permafrost thermal stability beneath the embankment in permafrost regions,as well as for improving the embankment stability and operational safety of the qinghai-Tibet Railway.

关键词： qinghai-Tibet Railway U-shaped crushed rock embankment Climate change Permafrost zone Ground temperature variation index Long-term coolingrole

Flower-like tin oxide membranes with robust three-dimensional channels for efficient removal of iron ions from hydrogen peroxide

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Chinese Journal of Chemical Engineering 2024年第1期65卷 1-7页

作者： Risheng Shen Shilong Li Yuqing Sun yuan bai Jian Lu Wenheng Jing State Key Laboratory of Materials-Oriented Chemical Engineering Nanjing Tech UniversityNanjing 210009China National Energy Group Science and Technology Research Institute Co. Ltd.Nanjing 210023China

Membrane technology has become the mainstream process for the production of electronic grade hydrogen peroxide(H_(2)O_(2)).But due to the oxidation degradation of the organic membranes(***)by the strong oxidative radicals(e.g.OH)generated via the activation of H_(2)O_(2)by iron ions(Fe^(3+)),the short effective lifetime of membranes remains a *** nano tin oxide(SnO_(2))has great potential for the removal of Fe^(3+)in strongly oxidative H_(2)O_(2)because of its ability to stabilize H2O_(2)and preferentially adsorb Fe^(3+).Herein,we have designed for the first time a flower-like robust SnO_(2)membrane on the ceramic support by in situ template-free one-step hydrothermal *** three-dimensional loose pore structure in the membrane built by interlacing SnO_(2)nanosheets endows the SnO_(2)membrane with a high specific surface area and abundant adsorption sites(AOH).Based on the coordination complexation and electrostatic attraction between the SnO_(2)surface and Fe^(3+),the membrane shows a high Fe3+removal efficiency(83%)and permeability(24 L·m^(-2)·h^(-1)·MPa^(-1))in H_(2)O_(2).This study provides an innovative and simple approach to designing robust SnO_(2)membranes for highly efficient removal of Fe^(3+)in harsh environments,such as strong oxidation conditions.

关键词： Hydrogen peroxide SnO_(2)membrane Adsorption Hydrothermal

Effects of gravel on the water absorption characteristics and hydraulic parameters of stony soil

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Journal of Arid Land 2024年第7期16卷 895-909页

作者： MA Yan WANG Youqi MA Chengfeng yuan Cheng bai Yiru Breeding Base for State Key Laboratory of Land Degradation and Ecological Restoration in Northwest China Ningxia UniversityYinchuan 750021China School of Geography and Planning Ningxia UniversityYinchuan 750021China School of Ecology and Environment Ningxia UniversityYinchuan 750021China

The eastern foothills of the Helan Mountains in China are a typical mountainous region of soil and gravel,where gravel could affect the water movement process in the *** study focused on the effects of different gravel contents on the water absorption characteristics and hydraulic parameters of stony *** stony soil samples were collected from the eastern foothills of the Helan Mountains in April 2023 and used as the experimental materials to conduct a one-dimensional horizontal soil column absorption *** experimental groups with gravel contents of 0%,10%,20%,30%,40%,and 50%were established to determine the saturated hydraulic conductivity(K_(s)),saturated water content(θ_(s)),initial water content(θ_(i)),and retention water content(θ_(r)),and explore the changes in the wetting front depth and cumulative absorption volume during the absorption *** Philip model was used to fit the soil absorption process and determine the soil water absorption *** the length of the characteristic wetting front depth,shape coefficient,empirical parameter,inverse intake suction and soil water suction were derived from the van Genuchten ***,the hydraulic parameters mentioned above were used to fit the soil water characteristic curves,unsaturated hydraulic conductivity(K_(θ))and specific water capacity(C(h)).The results showed that the wetting front depth and cumulative absorption volume of each treatment gradually decreased with increasing gravel *** with control check treatment with gravel content of 0%,soil water absorption rates in the treatments with gravel contents of 10%,20%,30%,40%,and 50%decreased by 11.47%,17.97%,25.24%,29.83%,and 42.45%,*** the gravel content increased,inverse intake suction gradually increased,and shape coefficient,K_(s),θ_(s),andθ_(r)gradually *** the same soil water content,soil water suction and K_(θ)gradually decreased with increasing gravel *** the same soil water s

关键词： stony soil gravel content water absorption characteristics hydraulic parameters one-dimensional horizontal soil column absorption experiment van Genuchten model eastern foothills of Helan Mountains

Effect of surfactant frequently used in soil flushing on oxygen mass transfer in micro-nano-bubble aeration system

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Chinese Journal of Chemical Engineering 2024年第3期67卷 174-181页

作者： Mei bai Zhibin Liu Zhu Liu Chenfei He Zhanhuang Fan Miaoxin yuan Jiangsu Key Laboratory of Urban Underground Engineering and Environmental Safety Southeast UniversityNanjing 211189China CECEP DADI(Hangzhou)Environmental Remediation Co. Ltd.Hangzhou 310020China

In-site soil flushing and aeration are the typical synergetic remediation technology for contaminated *** surfactant present in flushing solutions is bound to affect the aeration *** purpose of this study is to evaluate the effect of surfactant frequently used in soil flushing on the oxygen mass transfer in micro-nano-bubble(MNB)aeration ***,bio-surfactants and chemical surfactants were used to investigate their effects on Sauter mean diameter of bubble(dBS),gas holdup(ε),volumetric mass-transfer coefficient(kLa)and liquid-side mass-transfer coefficient(kL)in the MNB aeration ***,based upon the experimental results,the Sardeing's and Frossling's models were modified to describe the effect of surfactant on kL in the MNB *** results showed that,for the twenty aqueous surfactant solutions,with the increase in surfactant concentration,the value of dBS,kLa and kL decreased,while the value ofεand gas-liquid interfacial area(a)*** phenomena were mainly attributed to the synergistic effects of immobile bubble surface and the suppression of coalescence in the surfactant *** addition,with the presence of electric charge,MNBs in anionic surfactant solutions were smaller and higher in number than in non-ionic surfactant ***,the accumulation of surfactant on the gas-liquid interface was more conspicuous for small MNB,so the reduction of kL in anionic surfactant solutions was larger than that in non-ionic surfactant ***,the modified Frossling's model predicted the effect of surfactant on kL in MNB aeration system with reasonable accuracy.

关键词： Soil flushing Micro-nano-bubble aeration Bio-surfactant Mass transfer coefficient