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Based on non-targeted metabolomics for differential components screening of Rosae Chinensis Flos and Rosae Rugosae Flos and their quality evaluation

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Traditional Medicine Research 2025年第2期10卷 1-15页

作者： Xu Liang Ni-Hui Zhang Zhi-Lai Zhan Guang-lu chang Yan Gao Xia Li Wen-Yuan Gao School of Pharmaceutical Science and Technology Faculty of MedicineTianjin UniversityTianjin 300193China State Key Laboratory for Quality Ensurance and Sustainable Use of Dao-di Herbs China Academy of Chinese Medical SciencesBeijing 100700China Key Laboratory of Modern Chinese Medicine Resources Research Enterprises Tianjin 300402China

Background:Rosa chinensis *** Rosa rugosa *** not only of ornamental value,but also edible flowers and the flower buds have been listed in the Chinese Pharmacopoeia as traditional *** two plants have some differences in efficacy,but the flower buds are easily confused for similar *** addition,large-scale cultivation of ornamental rose flowers may lead to a decrease in the effective components of medicinal ***,it is necessary to study the chemical composition and make quality evaluation of Rosae Chinensis Flos(Yueji)and Rosae Rugosae Flos(Meigui).Methods:In this study,40 batches of samples including Meigui and Yueji from different regions in China were collected to establish high-performance liquid chromatography ***,the fingerprints data was analyzed using principal component analysis,hierarchical cluster analysis,and partial least squares discriminant analysis analysis chemometrics to obtain information on intergroup differences,and non-targeted metabolomic techniques were applied to identify and compare chemical compositions of samples which were chosen from groups with large *** compounds were screened by orthogonal partial least-squares discriminant analysis and S-plot,and finally multi-component quantification was performed to comprehensively evaluate the quality of Yueji and ***:The similarity between the fingerprints of 40 batches roses and the reference print R was 0.73 to 0.93,indicating that there were similarities and differences between the *** principal component analysis and hierarchical cluster analysis of fingerprints data,the samples from different origins and varieties were intuitively divided into four *** least-squares discriminant analysis analysis showed that Meigui and Yueji cluster into two categories and the model was reliable.A total of 89 compounds were identified by high resolution mass spectrometry,mainly were flavonoids and flavon

关键词： Rosa chinensis Jacq. Rosa rugosa Thunb. metabolomics chemometrics multiple component quantification quality evaluation

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Surface Properties and Hydrogen Bonds of Mono-functional Polybenzoxazines with Different N-substituents

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Chinese Journal of Polymer Science 2016年第8期34卷 919-919,920-932页

作者： Juan Liu Xin lu 辛忠 chang-lu Zhou School of Chemical Engineering East China University of Science and Technology

A series of mono-functional benzoxazine monomers with different N-substituents were synthesized from phenol, formaldehyde, and various amines （ammonia, methylamine, n-butylamine, dodecylamine）, named P-am, P-m, P-b, and P-da, respectively. The surface properties of these polybenzoxazine films were proven by contact angle measurements. The hydrogen bond network of the polybenzoxazine systems was studied using the FTIR spectra. And the results showed that the surface free energy increased with increasing the fraction of intermolecular hydrogen bonding when the N-substituent was an alkyl chain. However, the rule was not suitable when the N-substituent was H. That was because there was one more kind of intramolecular hydrogen bond in the poly（P-am）. Based on these findings, we proposed that both the N-substituent alkyl group and the fraction of intermolecular hydrogen bonding had effects on the surface free energy.

关键词： Polybenzoxazine Mono-functional N-substituents Surface free energy Hydrogen bonding.

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Quark Condensate in the Strange Matter

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Communications in Theoretical Physics 2003年第5期39卷 593-596页

作者： lu-chang-Fang luXiao-lu DepartmentofPhysics SichuanuniversityChengdu610064China DepartmentofPhysics SichuanuniversityChengdu610064China InstituteofTheoreticalPhysics AcademiaSinicaP.O.Box2735Beijing100080China

In a nonlinear chiral SU(3) framework, we investigate the quark condensate in the strange matter including and Λ, making use of chiral symmetry spontaneous breaking Lagrangian and mean-field approximation. The results show that the chiral symmetry is restored partially when the strange matter density increases and that plays a very important role in the strange matter which may approach the constituents of the neutron stars. In addition, we can find that the strange matter density where the π-condensate emerges leads to the ratio of the nucleon number to baryon number.

关键词： quark condensate chiral symmetry spontaneous breaking Lagrangian Hellmann-Feynman theory

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Possible Mechanism Associated with Herbicidal Activity of Soybean Meal Hydrolysate (SMH)

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Agricultural Sciences in China 2010年第6期9卷 854-860页

作者： YANG Jian lu chang-yi School of Applied Chemistry and Biotechnology Shenzhen Polytechnic Shenzhen 518055 P.R.China Environmental Science Research Center Xiamen University Xiamen 361005 P.R. China

Soybean meal hydrolyzate （SMH） has been proposed for use as a natural preemergence ***,the mechanism by which SMH exerts its herbicidal activity remains *** this paper,the herbicidal activities of SMH against perennial ryegrass （Lolium perenne L.） under non-sterile and sterile conditions were evaluated and the relationship between the molecular weight of the ultrafiltration （UF） fractions of SMH and their herbicidal activities were ***,the ammonia content changes of the media of SMH treatments 7 d after incubation were also *** results showed that SMH inhibited the radicle growth of germinating *** seeds in a dose-dependent manner under non-sterile ***,SMH in the concentrations investigated increased the radicle length and shoot length by 14-17% and 11-15% respectively under sterile *** ammonia contents in the SMH media at all treatments increased greatly from less than 0.01 mg L-1 to up to 11.86-41.37 mg L-1 after 7 d incubation under non-sterile ***,ammonia content did not change under sterile condition,proposing that the herbicidal activity might be caused by the free ammonia released from SMH by microbial *** was no difference on the perennial ryegrass radicle inhibition among the UF fractions of SMH on an equivalent N *** could be concluded that SMH exerted its herbicidal activity through the free ammonia released under non-sterile condition instead of by specific peptide（s） in SMH.

关键词： soybean meal hydrolysate herbicidal active mechanism ammonia

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Current Oscillation and dc-Voltage-Controlled Chaotic Dynamics in Semiconductor Superlattices

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Communications in Theoretical Physics 2006年第2期45卷 363-368页

作者： WANG chang lu Jing-Tao State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information Technology the Chinese Academy of Sciences Shanghai 200050 China

We report a detailed theoretical study of current oscillation and de-voltage-controlled chaotic dynamics in doped GaAs/AlAs resonant tunneling superlattices under crossed electric and magnetic fields. When the superlattice is biased at the negative differential velocity region, current self-oscillation is observed with proper doping concentration. The current oscillation mode and oscillation frequency can be affected by the dc voltage bias, doping density, and magnetic field. When an ac electric field with fixed amplitude and frequency is also applied to the system, different nonlinear properties show up in the external circuit with the change of dc voltage bias. We carefully study these nonlinear properties with different chaos-detecting methods.

关键词： semiconductor superlattices current oscillation chaotic dynamics

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Confinement characteristic of primary electrons with the variation of channel width in the discharge chamber of annular ion thruster

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Chinese Journal of Aeronautics 2021年第5期34卷 79-92页

作者： chang lu Guangqing XIA Bin SUN Yajie HAN State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of TechnologyDalian 116024China Key Laboratory of Advanced Technology for Aerospace Vehicles of Liaoning Province Dalian University of TechnologyDalian 116024China

In this paper,the confinement characteristic of primary electrons in the non-axisymmetric discharge chamber of annular ion thruster is investigated by a three-dimensional(3 D)non-self-consistent particle tracking model with Monte Carlo Collision(MCC)*** results show that:The density of primary electrons upstream of ion optics on cathode axis is about 5–50 times higher than that of the other side,which means that the density of primary electrons is obviously *** channel width has a significant effect on the average density and uniformity of primary *** average density can be increased by nearly 1.5 times under the appropriate channel width,meanwhile,the variance of density distribution can be reduced by more than 2 *** is because that increasing the channel width can improve the average confinement length of primary electrons ***,there is an infection point in the increase of primary electron average confinement length with the channel width,which caused by the significant change of magnetic field *** the case after the inflection point,primary electron mainly(more than 50%)moves to the channel center,which makes the average confinement length of primary electrons and their number in the discharge chamber increase largely.

关键词： Annular ion thruster Average confinement length Electric propulsion Ion thruster Primary electrons

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Ke Hsin Kuo:A distinguished scientist and great mentor

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Protein & Cell 2019年第2期10卷 79-86页

作者： Da-Neng Wang lu-chang Qin Skirball Institute of Biomolecular Medicine and Department of Cell BiologyNew York University School of Medicine540 First AvenueNew YorkNY 10016USA W.M.Keck Laboratory for Atomic Imaging and Manipulation Department of Physics and AstronomyUniversity of North CarolinaChapel HillNC 27599USA

Early years Professor Ke Hsin Kuo was bom in Beijing in 1923,and his childhood was spent in Harbin in northemstem China where his father worked as an engineer to build the local *** early education was at best characterized by frequent disruptions,the first of which being the"9.18 Incidenf of 1931 when the Japanese Kwantung Army launched an assault in Shenyang(Mukden)on the local Chinese troops and quickly took control of all the Northeastern Provinces(Manchuria).He moved to Tianjin in the spring of 1936,where he continued his education by enrolling in the famous Nankai High ***,his school life at Nankai was soon disrupted again by the eruption of full-scale war in July of 1937 after Japan attacked and occupied *** with his brothers,he fled to join his parents who had previously relocated to *** studied in Chongqing for four more years to complete his high school education,during which classes were constantly being disrupted due to the frequent bombings of the city by Japanese *** bombings not only left him with long lasting memories of the war,but also bore him a permanent burn scar on his back as a result of a bomb that exploded just meters away from him.

关键词： Professor childhood Manchuria

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Copper coordination-driven self-assembly and encapsulation of PCR reagents

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Chinese Chemical Letters 2024年第3期35卷 189-192页

作者： chang lu Jinkai Zheng Juewen Liu Institute of Food Science and Technology Chinese Academy of Agricultural SciencesBeijing 100193China Department of Chemistry Waterloo Institute for NanotechnologyUniversity of WaterlooWaterlooONN2L 3G1Canada

Polymerase chain reactions(PCR)are a very important tool for use in cloning,nucleic acid sequencing and diagnostic *** storage conditions of PCR reagents are limited to freezing and a lot of mixing steps are *** this paper,we report using metal ions to form coordination nanomaterials with the intrinsic components of the PCR reagents including dNTP,DNA primers and DNA polymerase as an integrated PCR reaction *** complete PCR reactions,users need only to dissolve the coordination nanomaterials with a buffer and add template DNA.A few transition metal ions were screened and Cu^(2+)was found to be the most effective metal ion for this *** the encapsulation efficiency of PCR reagents was measured,which can reach close to 100%for the primers and DNA polymerase,but only 10%for dNTP because dNTP was *** study also exhibited this integrated PCR reaction system can be used for DNA detection with a similar detection limit to the normal PCR,and showed good stability of encapsulated PCR nanomaterial after storage for a week.

关键词： Metal ions Coordination Encapsulation PCR Storage

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Reverence of Life in Teenagers’ Eyes

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Journal of Systems Science and Systems Engineering 2021年第3期30卷 363-379页

作者： Haoming Ye Yan Wang chang lu Xiaoguang Yang Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing100049China

This study investigates which factors determine the teenagers’attitudes toward human life among different ethnic groups,based on a unique survey data from Xinjiang juvenile students with their family,school and social *** find that environment factors and education efforts mainly affect the teenagers’attitudes to life value,but their ethnic groups have no *** of life does not come from which ethnic group one belongs in,but comes from one’s environment and *** of life need to be cultivated.

关键词： Reverence of life Xinjiang juvenile students environment factors education efforts

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Experimental and computational studies on flow behavior of gas-solid fluidized bed with disparately sized binary particles

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Particuology 2008年第2期6卷 59-71页

作者： Jinsen Gao Jian chang Chunxi lu Chunming Xu State Key Laboratory of Heavy Oil Processing China University of Petroleum Changping Beijing 102249 China

This paper presents experimental and computational studies on the flow behavior of a gas-solid fluidized bed with disparately sized binary particle mixtures. The mixing/segregation behavior and segregation efficiency of the small and large particles are investigated experimentally. Particle composition and operating conditions that influence the fluidization behavior of mixing/segregation are examined. Based on the granular kinetics theory, a multi-fluid CFD model has been developed and verified against the experimental results. The simulation results are in reasonable agreement with experimental data. The results showed that the smaller particles are found near the bed surface while the larger particles tend to settle down to the bed bottom in turbulent fluidized bed. However, complete segregation of the binary particles does not occur in the gas velocity range of 0.695-0.904 m/s. Segregation efficiency increases with increasing gas velocity and mean residence time of the binary particles, but decreases with increasing the small particle concentration. The calculated results also show that the small particles move downward in the wall region and upward in the core. Due to the effect of large particles on the movement of small particles, the small particles present a more turbulent velocity profile in the dense phase than that in the dilute phase.

关键词： Binary particles Distinct size difference Mixing Segregation Fluidized bed CFD

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