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New approach for chiral separation: from polysaccharide-based materials to chirality-responsive polymers

Science China Chemistry 2014年第11期57卷 1492-1506页

作者： DING peng CHANG BaiSong QING GuangYan SUN TaoLei State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology School of Chemistry Chemical Engineering and Life Science Wuhan University of Technology

Chiral separation that is closely related to daily life is a meaningful research. Polysaccharide-(e.g., cellulose, amylose derivatives) based chiral packing materials afford powerful chiral stationary phases(CSPs) toward a broad range of racemic compounds. However, considering the explosive growth of specific chiral drugs, the separation efficiencies of these CSPs need further improvement, which calls for new approaches and strategies. Smart polymers can change their physical or chemical properties dynamically and reversibly according to the external stimuli(e.g., thermo-, pH, solvent, ion, light, critical parameters for chromatographic separation) exerted on them, subsequently resulting in tunable changes in the macroscopic properties of materials. In addition to their excellent controllability, the introduction of chiral characteristics into the backbones or side-chains of smart polymers provides a promising route to realize reversibly conformational transition in response to the chiral analytes. This dramatic transition may significantly improve the performance of materials in chiral separation through modulating the enantioselective interactions between materials and analytes. with the help of chirality-responsive polymers, intelligent and switchable CSPs could be developed and applied in column-liquid chromatography. In these systems, the elution order or enantioselectivity of chiral drugs can be precisely modulated, which will help to solve many challenging problems that involve complicated enantiomers. In this paper we introduce some typical examples of smart polymers that serve as the basis for a discussion of emerging developments of CPSs, and then briefly outline the recent CSPs based on natural and certain synthetic polymers.

关键词： chiral separation chiral stationary phases(CSPs) enantioseparation HPLC smart polymer

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Simultaneous determination of 14 active constituents of Shengjiang xiexin decoction using ultrafast liquid chromatography coupled with electrospray ionization tandem mass spectrometry

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Acta Pharmaceutica Sinica B 2017年第2期7卷 193-201页

作者： Gang peng Huanyu Guan xiaoming wang Yue Shi Institute of Medicinal Plant Development Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100193China

An effective herbal medicinal prescription of Shengjiang xiexin decoction(SxD) was used in treating the inflammatory bowel disease in *** this study,an ultrafast liquid chromatography-tandem mass spectrometry(UFLC-MS/MS) method was developed to separate and to simultaneously determine14 major active ingredients in *** separation was successfully accomplished on an Acquity BEH C18(100 mm × 2.1 mm,1.7 μm) column using gradient elution with 0.1%(v/v) formic acid water(A) and 0.1%(v/v) formic acid in methanol(B).Negative and positive electrospray ionization tandem mass spectrometry was used to detect the 14 analytes using its selective reaction monitoring(SRM) mode.A good linear regression relationship for each analyte was obtained over the range from3.88 ng/mL to 4080 ng/*** precision was evaluated by intra-and inter-day assays with a relative standard deviation(RSD) of less than 6.25%.The recovery measured at three concentration levels varied from 98.72%to 103.47%.The overall limits of quantification(LOQ) ranged from 2.05 ng/mL to4.72 ng/*** method was successfully implemented in the qualitative and quantitative analyses of the14 chemical constituents in *** results showed that the developed UFLC-MS/MS method was linear and *** method could be used reliably as a quality control method for SxD.

关键词： Inflammatory bowel disease Quality control UFLC–MS/MS Determination Shengjiang xiexin decoction

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The Systematic Evaluation of Physicochemical and Biological Properties In Vitro and In Vivo for Natural Silk Fibroin Nanoparticles

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Advanced Fiber Materials 2022年第5期4卷 1141-1152页

作者： xinyi Li Mengjie Ye Yong‑E.Gao Shengxin Hou peng Jia peng xue Yuejun Kang Zhigang xu State Key Laboratory of Silkworm Genome Biology School of Materials and Energy and Chongqing Engineering Research Center for Micro‑Nano Biomedical Materials and DevicesSouthwest UniversityChongqing 400715People’s Republic of China Chongqing Key Laboratory of Soft‑Matter Material Chemistry and Function Manufacturing Southwest UniversityChongqing 400715People’s Republic of China

Nanoparticle-based theranostics has served as a preferential technology for diagnosis and treatment of ***,there are still massive challenges in constructing the ideal platform,which hopefully integrate various characteristics such as easy preparation,multiple utilization,and high therapeutic effect and safety into a single ***,we reported a drug delivery system-based on natural silk fibroin(denoted as SF NPs),and systematically evaluated the physicochemi-cal properties,biological properties and the biosafety assessment of SF *** in vitro and in vivo experimental results confirmed that SF NPs showed high stability,low blood hemolysis and the universal delivery ability of ***,the SF NPs could rapidly enter into cells due to its nanoscale size,and had a weak cytotoxicity against MCF-7,4T1 and L929 ***,the SF NPs showed enhanced tumor permeability in a simulative model of multicellular spheroids,combined with excellent in vivo biosafety and the negligible organ injury,demonstrate that SF-based nanomedicine presents the utilization potentiality for drug delivery and may provide a new view for cancer treatment.

关键词： Silk fibroin Drug delivery Biocompatibility Cytotoxicity Nanotheranostics

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Centralized control of parallel connected power conditioning system in electric vehicle charge-discharge and storage integration station

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Journal of Modern Power Systems and Clean Energy 2015年第2期3卷 269-276页

作者： Jiuqing CAI Changsong CHEN peng LIU Shanxu DUAN State Key Laboratory of Advanced Electromagnetic Engineering and Technology School of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhanChina

This study presents a centralized control scheme that coordinates parallel operations of power conditioning system(PCS)for the grid interactions of electric vehicles(EVs)in EV charge-discharge and storage integration *** issues for the control and operation of PCS under various operation modes are discussed,including vehicle to grid(V2G)mode,stand-alone mode and seamless transfer *** intelligent multi-mode charge-discharge method is utilized for the V2G mode,and the parallel control method based on communication network is adopted for the standalone *** addition,a novel seamless transfer strategy is proposed,which is able to implement PCS transition between V2G mode and stand-alone *** detailed process of the seamless transfer between the two modes is *** results are presented to show the performance and feasibility of this strategy.

关键词： Centralized control Power conditioning system(PCS) Charge-discharge and storage integration station Vehicle to grid(V2G) Seamless transfer

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A Zero-watermark Scheme Based on Quaternion Generalized Fourier Descriptor for Multiple Images

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Computers, Materials & Continua 2022年第5期71卷 2633-2652页

作者： Baowei wang weishen wang peng Zhao Naixue xiong School of Computer Science Nanjing University of Information Science and TechnologyNanjing210044China Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment Technology(CICAEET) Nanjing210044China Engineering Research Center of Digital Forensics Ministry of EducationNanjing210044China Department of Mathematics and Computer Science Northeastern State UniversityTahlequahOK74464USA

Most of the existing zero-watermark schemes for medical images are only appropriate for a single grayscale *** they protect a large number of medical images,repeating operations will cause a significant amount of time and storage ***,this paper proposes an efficient zero-watermark scheme for multiple color medical images based on quaternion generalized Fourier descriptor(QGFD).Firstly,QGFD is utilized to compute the feature invariants of each color image,then the representative features of each image are selected,stacked,and reshaped to generate a feature matrix,which is then binarized to get a binary feature *** information can be converted into the copyright image by using QR code technology,which contains more ***,the zero-watermark image is constructed by executing the xOR operation on the copyright image and the feature image scrambled by the Cat *** the experiment,different parameters are selected to determine the maximum number of images that the proposed scheme can protect simultaneously while achieving good *** experimental results demonstrate that the proposed scheme can effectively resist common attacks,geometric attacks and joint attacks,and effectively improve the operation efficiency of the algorithm,thus effectively decreasing the time and storage cost of copyright protection for lots of medical images.

关键词： Copyright protection color medical image zero-watermark QGFD

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Calibration and validation of a sand model considering the effects of wave-induced principal stress axes rotation

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Acta Oceanologica Sinica 2015年第7期34卷 105-115页

作者： LIU peng wANG Zhongtao LI xinzhong CHAN Andrew State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology General Research Institute of China National Offshore Oil Corporation Faculty of Science and Technology Federation University Australia

Principal stress axes rotation influences the stress-strain behavior of sand under wave loading. A constitutive model for sand, which considers principal stress orientation and is based on generalized plasticity theory, is proposed. The new model, which employs stress invariants and a discrete memory factor during reloading, is original because it quantifies model parameters using experimental data. Four sets of hollow torsion experiments were conducted to calibrate the parameters and predict the capability of the proposed model, which describes the effects of principal stress orientation on the behavior of sand. The results prove the effectiveness of the proposed calibration method.

关键词： principal stress axes rotation constitutive model hollow torsional shear experiment

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EFFECT OF TESTING ENVIRONMENT ON FRACTURING BEHAVIOR OF Fe_3Si BASED ALLOY

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Acta Metallurgica Sinica(English Letters) 2003年第2期16卷 104-109页

作者： J.H.peng G.L.Chen National Key Laboratory for Nuclear Fuel&Materials China Nuclear Power InstituteChengdu 610041ChinaState Key Laboratory for Advanced Metal MaterialsUniversity of Science&Technology BeijingBeijing 100083China

The mechanical behavior of Fes Si based alloy with B2 structure was studied by tension and fracture toughness test in various testing media. The fracture strength σb of Fe3Si alloy decreased in the following order: oxygen, air and hydrogen respectively. The fracture toughness in different testing environment showed that KIC in oxygen is 11.5±0.3MPa·m1/2, and is 8.6±0.4MPa·ml/2 in distilled water. The reduction of fracture toughness is contributed to the environmental reaction of Si with water. Addition of Al element in Fe3Si is not beneficial to improve the intrinsic ductility of Fe-14Si-3Al alloy. The scattering phenomenon of fracture strength was found, and explained by fracture mechanics. It was found by means of SEM that the fracture mode changed from transgranular in oxygen to intergranular in hydrogen gas and distilled water.

关键词： Fe3Si intermetallic mechanical behavior environmental em- brittlement

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P-wave tomography of crust and upper mantle under Southern California: Influence of topography of Moho discontinuity

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Acta Seismologica Sinica(English Edition) 2003年第6期16卷 577-587页

作者： HUANG Jin-li(黄金莉) ZHAO Da-peng(赵大鹏) Center for Analysis and Prediction China Seismological Bureau Beijing 100036 China Geodynamics Research Center Ehime University Matsuyama 790 Japan

we use 146 422 P-wave arrival times from 6 347 local earthquakes recorded by the Southern California SeismicNetwork to determine a detailed three-dimensional P-wave velocity structure at 0～35 km depth. we have takeninto account the Moho depth variations, which were obtained by seismological methods. Checkerboard tests sug-gest that our inversion results are reliable. Our models provide new information on regional geological structuresof Southern California. At shallow depths P-wave velocity structure correlates with surface geological features andexpresses well variations of surface topography of the mountains and basins. The velocity structure at each layer ischaracterized by block structures bounded by large faults. Ventura Basin, Los Angeles Basin, Mojave Desert, Pen-insular Ranges, San Joaquin Valley, Sierra Nevada, and Salton Trough show respectively all-round block. SanAndreas Fault becomes an obvious boundary of the region. To its southwest, the velocity is higher, and there arestrong heterogeneity and deeper seismicity; but to its northeast, the velocity is lower and shows less variation thanto the southwest, the seismicity is shallower. To investigate the effect of the Moho geometry we conducted inver-sions for two cases: one for flat Moho geometry, another for a Moho with lateral depth variations. we found thatthe topography of the Moho greatly affects the velocity structure of the middle and lower crust. when the Mohotopography is considered, a more reasonable tomographic result can be obtained and the resulting 3-D velocitymodel fits the data better.

关键词： Southern California Moho discontinuity 3-D P-wave velocity structure block feature seismicity

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Sodium Enrichment in Yellow Supergiants:a Perspective from the Uncertainties of Reaction Rates

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Chinese Journal of Astronomy and Astrophysics 2008年第6期8卷 700-706页

作者： Lei Zhao Qiu-He peng xin-Lian Luo Department of Astronomy Nanjing University Nanjing 210093 China

Sodium overabundance in yellow supergiants has stumped people for more than 20 years. The purpose of this paper is to explore this problem from the perspective of nuclear physics. we investigate carefully the CNO and NeNa cycles that are responsible for sodium production. we investigate some key reactions in the appropriate network. we show whether and how the sodium output can be affected by the rate uncertainties in these reactions. In this way, we evaluate if a reaction is important enough to deserve a better determination of its rate in terrestrial laboratories.

关键词： nuclear reactions nucleosynthesis stars: abundances supergiants

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Accurate and Computational Efficient Joint Multiple Kronecker Pursuit for Tensor Data Recovery

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Computers, Materials & Continua 2021年第8期68卷 2111-2126页

作者： weize Sun peng Zhang Jingxin xu Huochao Tan Guangdong Key Laboratory of Intelligent Information Processing College of Electronics and Information EngineeringShenzhen UniversityShenzhen518061China Department of Housing and Public works QueenslandAustralia Customer Service Centre Guangdong Power Grid CorporationGuangzhouChina

This paper addresses the problem of tensor completion from limited *** speaking,in order to achieve good recovery result,many tensor completion methods employ alternative optimization or minimization with SVD operations,leading to a high computational *** this paper,we aim to propose algorithms with high recovery accuracy and moderate computational *** is shown that the data to be recovered contains structure of Kronecker Tensor decomposition under multiple patterns,and therefore the tensor completion problem becomes a Kronecker rank optimization one,which can be further relaxed into tensor Frobenius-norm minimization with a constraint of a maximum number of rank-1 basis or *** the idea of orthogonal matching pursuit is employed to avoid the burdensome SVD *** on these,two methods,namely iterative rank-1 tensor pursuit and joint rank-1 tensor pursuit are *** economic variants are also included to further reduce the computational and storage complexity,making them effective for large-scale data tensor *** verify the proposed algorithms,both synthesis data and real world data,including SAR data and video data completion,are *** to the single pattern case,when multiple patterns are used,more stable performance can be achieved with higher complexity by the proposed ***,both results from synthesis and real world data shows the advantage of the proposed methods in term of recovery accuracy and/or computational complexity over the state-of-the-art *** conclude,the proposed tensor completion methods are suitable for large scale data completion with high recovery accuracy and moderate computational complexity.

关键词： Tensor completion tensor Kronecker decomposition Kronecker rank-1 decomposition

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