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Identification and screening of cardiac glycosides in Streptocaulon griffithii using an integrated data mining strategy based on high resolution mass spectrometry

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Chinese Journal of Natural Medicines 2018年第7期16卷 546-560页

作者： zhu xiao-Yu LIU Jia-zhuo DONG Zhen-Huan feng feng LIU Wen-Yuan Key Laboratory of Drug Quality Control and Pharmacovigilance Ministry of Education China Pharmaceutical University Key Laboratory of Biomedical Functional Materials China Pharmaceutical University

The present study was designed to develop a practical strategy to tackle the problem of lacking standard compounds and limited references for identifying structure-related compounds in Streptocaulon griffithii Hook. f., especially those in trace concentrations, with a focus on antitumor activity. The cardiac glycosides(CGs)-enriched part was determined using in vitro bioactive assays in three cancer cell lines and then isolated using macroporous resins. The MS and MS/MS data were acquired using a high performance liquid chromatography coupled with hybrid quadrupole-time of flight(HPLC-Q-TOF-MS) system. To acquire data of trace compound in the extract, a multiple segment program was applied to modify the HPLC-Q-TOF-MS method. A mass defect filter(MDF) approach was employed to make a primary MS data filtration. Utilizing a MATLAB program, the redundant peaks obtained by imprecise MDF template calculated with limited references were excluded by fragment ion classification, which was based on the ion occurrence number in the MDF-filtered total ion chromatograms(TIC). Additionally, the complete cleavage pathways of CG aglycones were proposed to assist the structural identification of 29 common fragment ions(CFIs, ion occurrence number ≥ 5) and diagnostic fragment ions(DFIs, ion occurrence number < 5). As a result, 30 CGs were filtered out from the MDF results, among which 23 were identified. This newly developed strategy may provide a rapid and effective tool for identifying structure-related compounds in herbal medicines.

关键词： Streptocaulongriffithii Cardiac glycosides Mass defect filter HPLC-Q-TOF-MS

Ascorbic Acid Assisted Green Route for Synthesis of Water Dispersible Carbon Dots

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Chemical Research in Chinese Universities 2013年第3期29卷 401-403页

作者： NAWAZ Faisal WANG Liang zhu Long-feng MENG Xiang-ju xiao feng-Shou State Key Laboratory of Inorganic Synthesis and Preparative Chemistry Jilin University Changehun 130012 P. R. China Department of Chemistry Zhejiang University Hangzhou 310028 P. R. China

Conventional quantum dots inherently carry the risk of cytotoxicity. Considering the biomedical limitations, an amino acid and vitamin were utilized to prepare highly luminescent carbon dots. Ascorbic acid and lysine were used to synthesize water soluble carbon dots which are highly hiocompatible as both reactants and essential nutrients.

关键词： Carbon dot Ascorbic acid Hydrothermal synthesis Lysine Green synthesis Water dispersible

Fluorescence microscopic morphology and inhibition ratestudies on apoptosis of osteosarcoma cells induced by ^(153)Sm

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Nuclear Science and Techniques 2000年第4期11卷 263-266页

作者： zhu Shou-Peng, xiao Dong, HAN xiao-feng (Suzhou Medical College, Sizhou 215007) 苏州医学院江苏苏州 215007

The apoptosis of osteosarcoma cells treated with irradiation by 153Sm-EDTMP was studied. The morphological changes in osteosarcoma cells were observed by fluorescence microscopy. It was found that osteosarcoma cells exposed with 153Sm-EDTMP displayed significant nuclear fragmentation and marked pyknosis. With the prolongation of observing period, the membrane bound apoptotic bodies formation was observed. It should be noted, that with the lengthening of irradiation time by 153Sm-EDTMP, the inhibition rate of proliferation of osteosarcoma cells increased progressively.

关键词：钐153 ^153Sm-EDTMP 放射性核素标记荧光显微镜胃肉瘤肿瘤细胞细胞凋亡

Deformed-Skyrme-Hartree-Fock Calculation on C Isotope

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Chinese Physics Letters 1998年第6期15卷 404-406页

作者： SHEN Yao-song zhu xiao-feng REN Zhong-zhou CCAST(World Laboratory) P.O.Box 8730Beijing 100080 Graduate School China Academy of Engineering PhysicsBeijing 100088 Institute of Applied Physics and Computational Mathematics Beijing 100088 China Institute of Atomic Energy Beijing 102413 Department of Physics Nanjing UniversityNanjing 210008

The ground state properties of deformed nuclei of C isotope are investigated by the Skyrme-Hartree-Fock theory with new force parameters SKI4 of Reinhard and Flocard[***.A 584(1995)467].Calculations show that the deformed-Skyrme-Hartree-Fock theory with above force parameters provides a good description on the binding energy,the various radii and deformation parameters of C *** figure of the evolution of deformation for whole C isotope chain is plotted.A detailed discussion on numerical results is provided in the paper.

关键词： Hartree deformed Skyrme

Influence of pump noise on the health of fish in a large pumping station

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Journal of Hydrodynamics 2022年第3期34卷 522-531页

作者： Fan Zhang Lu-feng zhu xiao-tao Shi Ke Chen Desmond Appiah Shou-qi Yuan Jin-feng Zhang National Research Center of Pumps Jiangsu UniversityZhenjiang212013China Hubei International Science and Technology Cooperation Base of Fish Passage China Three Gorges UniversityYichang443002China

The axial flow pump,characteristic of a large flow,is widely used in pumping stations of hydraulic ***,the internal noise of the axial-flow pump of a high sound pressure level is notable,with a great influence on the fishing *** present,the studies of the impact of the noise on fish are mainly focused on the explosion,the offshore wind power plant,the ship and other fields,with little attention on the noise generated by the pumping *** paper applies the combination of the computational fluid dynamics and the Actran to study the sound pressure level distribution in the high-noise area inside the axial-flow pump and the noise distribution in the downstream areas of the pumping *** comparisons are made of the hearing threshold and the hearing damage threshold of fish,and it is revealed that the noise inside the axial-flow pump exceeds the hearing damage threshold of fish,which could lead to the hearing damage of over-pumped ***,the noises emitted from the pumping station to the downstream are beyond the fish hearing threshold and will also have a significant impact on the fish around the pumping *** study can provide a reference for studying the impact of the noise generated by various large-scale water transfer projects on fish.

关键词： Fish numerical analysis axial flow pump ACTRAN hearing impairment

Line profile studies of hydrodynamical models of cometary compact H II regions

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Research in Astronomy and Astrophysics 2015年第6期15卷 828-848页

作者： feng-Yao zhu Qing-feng zhu Department of Astronomy University of Science and Technology of China Key Laboratory for Research in Galaxies and Cosmology University of Science and Technology of China Chinese Academy of Sciences

We simulate the evolution of cometary H II regions based on several champagne flow models and bow shock models, and calculate the profiles of the [Ne II] fine-structure line at 12.81 μm, the H30α recombination line and the [Ne III] finestructure line at 15.55 μm for these models at different inclinations of 0°, 30° and 60°. We find that the profiles in the bow shock models are generally different from those in the champagne flow models, but the profiles in the bow shock models with lower stellar velocity （≤ 5 km s^-1） are similar to those in the champagne flow models. In champagne flow models, both the velocity of peak flux and the flux weighted central velocities of all three lines point outward from molecular clouds. In bow shock models, the directions of these velocities depend on the speed of stars. The central velocities of these lines are consistent with the stellar motion in the high stellar speed cases, but they are opposite directions from the stellar motion in the low speed cases. We notice that the line profiles from the slit along the symmetrical axis of the projected 2D image of these models are useful for distinguishing bow shock models from champagne flow models. It is also confirmed by the calculation that the flux weighted central velocity and the line luminosity of the [Ne III] line can be estimated from the [Ne II] line and the H30α line.

关键词： H II regions -- ISM kinematics and dynamics clusters -- line profiles

Heating graphene to incandescence and the measurement of its work function by the thermionic emission method

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Nano Research 2014年第4期7卷 553-560页

作者： feng zhu State Key Laboratory of Low-Dimensional Quantum Physics Department of Physics and Tsinghua-Foxconn Nanotechnology Research Center Tsinghua University Beijing 100084 China Collaborative Innovation Center of Quanturn Matter Beijing 100084 China

The work function （WF） of graphene is an essential parameter in graphene electronics. We have derived the WF of graphene by the thermionic emission method. Chemical vapor deposition （CVD）-grown single-layered polycrystalline graphene on copper foil is transferred to a cross-stacked carbon nanotube （CNT） film drawn from a super-aligned multiwalled CNT array. By decreasing the pore size of the CNT film, the as-prepared CNT-graphene film （CGF） can be Joule heated to a temperature as high as 1,800 K in vacuum without obvious destruction in the graphene structure. By studying the thermionic emission, we derive the WF of graphene, ranging from 4.7 to 4.8 eV with the average value being 4.74 eV. Because the substrate influence can be minimized by virtue of the porous nature of the CNT film and the influence of adsorbents can be excluded due to the high temperature during the thermionic emission, the measured WF of graphene can be regarded as intrinsic.

关键词： graphene carbon nanotube thermionic emission work function

Long-term adaptive evolution of Shewanella oneidensis MR-1 for establishment of high concentration Cr(Ⅵ) tolerance

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Frontiers of Environmental Science & Engineering 2020年第1期14卷 65-75页

作者： Yong xiao Changye xiao feng Zhao CAS Key Laboratory of Urban Pollutant Conversion Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China University of Chinese Academy of Sciences Beijing 100049China

Acclimation is the main method to enhance the productivity of microorganisms in environmental biotechnology,but it remains uncertain how microorganisms acquire resistance to high concentrations of pollutants during long-term *** oneidensis MR-1 was acclimated for 120 days with increasing hexavalent chromium(Cr(VI))concentrations from 10 to 190 mg/*** bacterium was able to survive from the highly toxic Cr(VI)environment due to its enhanced capability to reduce Cr(VI)and the increased cell membrane *** sequenced 19 complete genomes from 7 populations of MR-1,including the ancestral strain,the evolved strains in Cr(VI)environment on days 40,80 and 120 and their corresponding controls.A total of 27,49 and 90 single nucleotide polymorphisms were found in the Cr(VI)-evolved populations on days 40,80 and 120,*** substitutions were clustered according to gene functions,and the gene mutations related to integral components of the membrane,including efflux pumps and transporters,were the key determinants of chromate *** addition,MR-1 strengthened the detoxification of Cr(VI)through gene variations involved in adenosine triphosphate binding,electron carrier activity,signal transduction and DNA *** results provide an in-depth analysis of how Cr(VI)resistance of *** MR-1 is improved by acclimation,as well as a genetic understanding of the impact of longterm exposure of microorganisms to pollution.

关键词： Environmental biotechnology Acclimation Chromate resistance Efflux pumps Detoxification

Emergy evaluation of aromatics production from methanol and naphtha

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Chinese Journal of Chemical Engineering 2022年第6期35卷 134-141页

作者： Siyue Ren xiao feng School of Chemical Engineering and Technology Xi’an Jiaotong UniversityXi’an 710049China

Aromatics are traditionally produced by the catalytic reforming of ***,with the demand of aromatics increasing and the reserves of petroleum resources declining,measures should be made to reduce the dependence of aromatics production on petroleum ***-to-aromatics is proved to be an effective way to replace traditional naphtha-to-aromatics *** order to compare the economic and environmental performance of aromatics production from naphtha and methanol,this paper carries out an emergy evaluation for each system by sorting out the simulation and literature *** on the emergy data collected,the emergy indices of each system are *** results show that the sustainabilities of methanol-to-aromatics systems are higher than that of the naphtha-toaromatics system,indicating the advantages of aromatics production from *** the methanol-to-aromatics systems,the aromatics from biomass-methanol system has the highest sustainability,indicating that the biomass based methanol-to-aromatics system is worth *** sustainability indexes of methanol-to-aromatics systems based on coal and coke oven gas are less than 1,which means ***,the sustainability of natural gas based system is slightly higher than *** economic and environmental benefits of these systems can be optimized by improving resource utilization and reducing investment ***,the combination of different raw materials for methanol production should be considered.

关键词： Aromatics production Naphtha Methanol Emergy Sustainability