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Utilizing 3D DOSY NMR in the characterization of organic compounds in coal chemical wastewater

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Magnetic Resonance Letters 2022年第2期2卷 69-79,I0002页

作者： Hui Ma christian M.Pedersen Qi Zhao Shiyu Jia Bin Yuan Xianglin Hou Yingxiong Wang Shanxi Engineering Research Center of Biorefinery Institute of Coal ChemistryChinese Academy of SciencesTaiyuan030001China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing100049China Department of Chemistry University of CopenhagenUniversitetsparken 5DK-2100CopenhagenDenmark State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Center for Magnetic ResonanceWuhan Institute of Physics and MathematicsInnovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan430071China

Coal chemical wastewater(CCW)with the features of high toxicity and poor biodegradability is a big issue in environmental remediation,posing a great threat to aquatic ecosystems and to human *** complex molecular mixtures are notoriously difficult to characterize without initial physical ***,we present the 3D diffusion ordered spectroscopy(DOSY)analysis for CCW using DOSY-COSY and DOSY-HSQC methods,the advantages of this strategy have been demonstrated in the analysis of mixtures of aliphatic oxygenates and aromatic compounds,before being implemented on a genuine CCW sample in this *** results showed that 3D DOSY is a robust and reliable tool for providing superior resolution and virtual separation of complex pollutants,and can be used as a general approach for structural elucidation.

关键词： Coal chemical wastewater 3D DOSY NMR Analysis Separation Structural characterization

Characteristics of gravity signal and loading effect in China

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Geodesy and Geodynamics 2015年第4期6卷 280-285页

作者： Yi Shuang Sun Wenke Key Laboratory of Computational Geodynamics University of Chinese Academy of Sciences

The complex geographical environment in China makes its gravity signals *** work gives a comprehensive representation and explanation in secular trend of gravity change in different regions,the key features of which include positive trend in inner Tibet Plateau and South China and negative trend in North China plain and high mountain Asia（HMA）.We also present the patterns of amplitudes and phases of annual and semiannual *** mechanism underlying the semiannual period is explicitly *** displacement in three directions expressed in terms of geo-potential spherical coefficients and load Love numbers are given.A case study applied with these equations is *** results show that Global Positioning System（GPS） observations can be used to compare with Gravity Recovery and Climate Experiment（grace） derived displacement and the vertical direction has a signal-noise-ratio of about one order of magnitude larger than the horizontal directions.

关键词： Gravity change Loading effect Gravity Recovery and Climate Experiment (grace)Load love number Global Positioning System (GPS) Seasonal variation Gravity trend in China Comparison of grace and GPS

Application of Accelerometer Data in Precise Orbit Determination of grace-A and-B

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Chinese Journal of Astronomy and Astrophysics 2008年第5期8卷 603-610页

作者： Dong-Ju Peng Bin Wu Shanghai Astronomical Observatory CAS Shanghai 200030 China Graduate University of Chinese academy of Sciences Beijing 100049 China

We investigate how well the grace satellite orbits can be determined using the on- board GPS data combined with the accelerometer data. The preprocessing of the accelerometer data and the methods and models used in the orbit determination are presented. In order to assess the orbit accuracy, a number of tests are made, including external orbit comparison, and through Satellite Laser Ranging （SLR） residuals and K-band ranging （KBR） residuals. It is shown that the standard deviations of the position differences between the so-called precise science orbits （PSO） produced by GFZ, and the single-difference （SD） and zero-difference （ZD） dynamic orbits are about 7 cm and 6 cm, respectively. The independent SLR validation indicates that the overall root-mean-squared （RMS） errors of the SD solution for days 309 - 329 of 2002 are about 4.93cm and 5.22cm, for grace-A and B respectively; the overall RMS errors of the ZD solution are about 4.25 cm and 4.71 cm, respectively. The relative accuracy between the two grace satellites is validated by the KBR data to be on a level of 1.29cm for the SD, and 1.03 cm for the ZD solution.

关键词： celestial mechanics- ephemerides - methods numerical

Conductance of a single molecule C_(60)-SnPc heterojunction

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Chinese Chemical Letters 2022年第2期33卷 1074-1076页

作者： Yifan Wang Mingjun Zhong Jie Li Hao Tang Richard Berndt Yajie Zhang Shimin Hou Yongfeng Wang Key Laboratory for the Physics and Chemistry of Nanodevices and Center for Carbon-based Electronics Department of ElectronicsPeking UniversityBeijing 100871China CEMES-CNRS Boîte Postale 94347Toulouse 31055France Institut für Experimentelle und Angewandte Physik Christian-Albrechts-Universität zu KielKiel D-24098Germany Beijing academy of Quantum Information Sciences Beijing 100193China Institute of Spin Science and Technology South China University of TechnologyGuangzhou 511442China

Geometries of molecule-molecule interfaces strongly influence the current passing from one molecule to another. The contact conductance of molecule-molecule junctions which consist of fullerene and tin phthalocyanine molecules is investigated with a low-temperature scanning tunneling microscope. Two types of molecules are deposited onto Cu(111). Fullerene molecules are transferred to tips through controlled contact of STM tips on molecules. The molecule-molecule junctions are formed by approaching fullereneterminated tips to tin phthalocyanine molecules on Cu(111). Our experimental method can be extended to study the intermolecular charge transport of a range of molecular junctions.

关键词： Single-molecule electronics Switch C_(60) Phthalocyanine STM

Theories and applications of earthquake-induced gravity variation:Advances and perspectives

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Earthquake Science 2023年第5期36卷 376-415页

作者： He Tang Wenke Sun Key Laboratory of Computational Geodynamics College of Earth and Planetary SciencesUniversity of Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Geodesy and Earth’s Dynamics Innovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430077China

Earthquake-induced gravity variation refers to changes in the earth’s gravity field associated with seismic *** recent years,development in the theories has greatly promoted seismic deformation research,laying a solid theoretical foundation for the interpretation and application of seismological gravity *** terrestrial gravity measurements continue to play a significant role in studies of interseismic,co-seismic,and post-seismic gravity field *** instance,superconducting gravimeter networks can detect co-seismic gravity change at the sub-micro Gal *** the same time,the successful launch of satellite gravity missions(e.g.,the Gravity Recovery and Climate Experiment or grace)has also facilitated applied studies of the gravity variation associated with large earthquakes,and several remarkable breakthroughs have been *** progress in gravity observation technologies(e.g.,grace and superconducting gravimetry)and advances in the theories have jointly promoted seismic deformation studies and raised many new research *** example,superconducting gravimetry has played an important role in analyses of episodic tremor,slow-slip events,and interseismic strain patterns;the monitoring of transient gravity signals and related theories have provided a new perspective on earthquake early warning systems;the mass transport detected by the grace satellites several months before an earthquake has brought new insights into earthquake prediction methods;the use of artificial intelligence to automatically identify tiny gravity change signals is a new approach to accurate and rapid determination of earthquake magnitude and ***,many significant breakthroughs have been made in recent years,in terms of the theory,application,and observation *** article summarizes the progress,with the aim of providing a reference for seismologists and geodetic researchers studying the phenomenon of gravity variation,advances in

关键词： earthquake-induced gravity variation seismic dislocation theory time-varying gravity satellite gravity missions pre-P gravity signals superconducting gravimetry

Elevated CO2 differentially affects tobacco and rice defense against lepidopteran larvae via the jasmonic acid signaling pathway

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Journal of Integrative Plant Biology 2018年第5期60卷 412-431页

作者： Chengkai Lu Jinfeng qi christian Hettenhausen Yunting Lei Jingxiong Zhang Mou Zhang Cuiping Zhang Juan Song Jing Li Guoyan Cao Saif ul Malook Jianqiang Wu Department of Economic Plants and Biotechnology Yunnan Key Laboratory for Wild Plant Resources Kunming Institute of Botany the Chinese Academy of Sciences Kunming 650201 China University of Chinese academy of Sciences Beijing 100049 China College of Plant Protection Yunnan Agriculture University Kunming 650201 China

Atmospheric CO2 levels are rapidly increasing due to human activities. However, the effects of elevated CO2 （ECO2） on plant defense against insects and the underlying mechanisms remain poorly understood. Here we show that ECO2 increased the photosynthetic rates and the biomass of tobacco and rice plants, and the chewing lepidopteran insects Spodoptera litura and Mythimna separata gained less and more mass on tobacco and rice plants, respectively. Consistently, under ECO2, the levels of jasmonic acid （JA）, the main phytohormone controlling plant defense against these lepidopteran insects, as well as the main defense-related metabolites, were increased and decreased in insectdamaged tobacco and rice plants. Importantly, bioassays and quantification of defense-related metabolites in tobacco and rice silenced in JA biosynthesis and perception indicate that ECO2 changes plant resistance mainly by affecting the JA pathway. We further demonstrate that the defensive metabolites, but not total N or protein, are the main factors contributing to the altered defense levels under ECO2. This study illustrates that ECO2 changes the interplay between plants and insects, and we propose that crops should be studied for their resistance to the major pests under ECO2 to predict the impact of ECO2 on future agroecosystems.

关键词： Georg Jander Cornell University USA

Physical analysis on improving the recovery accuracy of the Earth's gravity field by a combination of satellite observations in along-track and cross-track directions

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Chinese Physics B 2014年第10期23卷 633-640页

作者：郑伟许厚泽钟敏员美娟 State Key Laboratory of Geodesy and Earth’s Dynamics Institute of Geodesy and Geophysics Chinese Academy of Sciences College of Science Wuhan University of Science and Technology

The physical investigations on the accuracy improvement to the measurement of the Earth＇s gravity field recovery are carried out based on the next-generation Pendulum-A/B out-of-plane twin-satellite formation in this paper. Firstly, the Earth＇s gravity field complete up to degree and order 100 is, respectively, recovered by the collinear and pendulum satellite formations using the orbital parameters of the satellite and the matching accuracies of key payloads from the twin grace satellites. The research results show that the accuracy of the Earth＇s gravity field model from the Pendulum-A/B satellite formation is about two times higher than from the collinear satellite formation, and the further improvement of the determination accuracy of the Earth＇s gravity field model is feasible by the next-generation Pendulum-A/B out-of-plane twin-satellite formation. Secondly, the Earth＇s gravity field from Pendulum-A/B complete up to degree and order 100 is accurately recovered based on the orbital parameters of the satellite （e.g., an orbital altitude of 400 km, an intersatellite range of 100 km, an orbital inclination of 89° and an orbital eccentricity of 0.001）, the matching accuracies of space- borne instruments （e.g. 10-6 m in the intersatellite range, 10-3 m in the orbital position, 10-6 m/s in orbital velocity, and 10-11 m/s2 in non-conservative force）, an observation time of 30 days and a sampling interval of 10 s. The measurement accuracy of the Earth＇s gravity field from the next-generation Pendulum-A/B out-of-plane twin-satellite formation is full of promise for being improved by about l0 times compared with that from the current grace satellite formation. Finally, the physical requirements for the next-generation Pendulum-A/B out-of-plane twin-satellite formation are analyzed, and it is proposed that the satellite orbital altitude be preferably designed to be close to 400±50 km and the matching precision of key sensors from the Pendulum-A/B mission be about one ord

关键词： twin pendulum-MB satellites collinear and pendulum satellite formations along-cross-track ob-servations physical analysis satellite gravity recovery

Enhanced diagnostic workup increases pathological findings in patients with acute ischaemic stroke:results of the prospective HEBRAS study

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Stroke & Vascular Neurology 2024年第2期9卷 145-152,I0414-I0425页

作者： Simon Hellwig Thomas Krause Jan F Scheitz Juliane Herm Ulrike Grittner Nadja Jauert Jochen B Fiebach Mario Kasner Wolfram Doehner Matthias Endres Rolf Wachter Thomas Elgeti christian H Nolte Karl Georg Haeusler Department of Neurology with Experimental Neurology Charité-Universitätsmedizin Berlincorporate member of Freie Universität Berlin and Humboldt-Universität zu BerlinBerlinGermany Center for Stroke Research Berlin BerlinGermany Berlin Institute of Health at Charité–Universitätsmedizin Berlin BIH Biomedical Innovation AcademyBerlinGermany Department of Neurology Jüdisches Krankenhaus BerlinBerlinGermany German Center for Cardiovascular Diseases(DZHK) Partner Site BerlinBerlinGermany Institute of Biometry and Clinical Epidemiology Charité-Universitätsmedizin BerlinBerlinGermany BIH Center for Regenerative Therapies(BCRT) Berlin Institute of Health at Charité–Universitätsmedizin BerlinBerlinGermany Department of Cardiology Charité-Universitätsmedizin BerlinBerlinGermany Department of Cardiology Campus Benjamin FranklinCharité-Universitätsmedizin BerlinBerlinGermany German Center for Neurodegenerative Diseases(DZNE) Partner Site BerlinBerlinGermany Department of Cardiology University Hospital LeipzigLeipzigGermany Department of Radiology Charité-Universitätsmedizin BerlinBerlinGermany Department of Neurology University Hospital WürzburgWürzburgGermany

Background Stroke aetiology remains cryptogenic in a relevant proportion of patients with acute ischaemic stroke(AIS).We assessed whether enhanced diagnostic workup after AIS yields a higher rate of prespecified pathological findings compared with routine diagnostic care *** Hospitalised patients with AIS were prospectively enrolled in the investigator-initiated observational HEart and BRain Interfaces in Acute Ischaemic Stroke(HEBRAS)study at the Charité,Berlin,*** with AIS without known atrial fibrillation(AF)underwent cardiovascular MR imaging(CMR),MR-angiography of the aortic arch and prolonged Holter-ECG monitoring on top of routine diagnostic *** Among 356 patients with AIS(mean age 66 years,37.6%female),enhanced workup yielded a higher rate of prespecified pathological findings compared with routine care(17.7%vs 5.3%;p<0.001).Consequently,fewer patients were classified as cryptogenic after enhanced diagnostic workup(38.5%vs 45.5%,p<0.001).Routine care included echocardiography in 228(64.0%)*** was successfully performed in 292(82.0%)patients and revealed more often a prespecified pathological finding compared with routine echocardiography(16.1%vs 5.3%).Furthermore,study-related ECG monitoring(median duration 162 hours(IQR 98–210))detected AF in 16(4.5%)patients,while routine monitoring(median duration 51 hours(IQR 34–74))detected AF in seven(2.0%)*** Enhanced diagnostic workup revealed a higher rate of prespecified pathological findings in patients with AIS compared with routine diagnostic care and significantly reduced the proportion of patients with cryptogenic *** registration number NCT02142413.

关键词： routine patients prospective

Efficient and rapid accuracy estimation of the Earth's gravitational field from next-generation GOCE Follow-On by the analytical method

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Chinese Physics B 2013年第4期22卷 563-570页

作者：郑伟许厚泽钟敏刘成恕员美娟 State Key Laboratory of Geodesy and Earth's Dynamics Institute of Geodesy and Geophysics Chinese Academy of Sciences Department of Applied Physics Wuhan University of Science and Technology

Firstly, a new analytical error model of the cumulative geoid height using the three-dimensional diagonal tensors of satellite gravity gradiometry （SGG） is introduced based on the variance-covariance matrix principle. Secondly, a study for the requirements demonstration on the next-generation GOCE Follow-On satellite gravity gradiometry system is developed using different satellite orbital altitudes and measurement accuracies of satellite gravity gradiometer by the new analytical error model of SGG. The research results show that it is preferable to design satellite orbital altitudes of 300 km–400km and choose the measurement accuracies of 10-13/s2 –10-15/s2 from satellite gravity gradiometer. Finally, the complementarity of the four-stage satellite gravity missions, including past CHAMP, current grace, and GOCE, and next-generation GOCE Follow-On, is contrastively demonstrated for precisely recovering the Earth’s full-frequency gravitational field with high spatial resolution.

关键词： GOCE Follow-On satellite analytical method requirements demonstration satellite gravity gradiometry Earth’s gravitational field