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Light-responsive Self-Immolative L-glutamic Acid-based Polyester Nanoparticles for Controlled Drug Release via Passerini Three-Component Polymerization

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Chinese Journal of Polymer Science 2024年第5期42卷 570-578,I0005页

作者： Xiao-Fei Sun Xu Zhang Shu-Ping Song Ya-Qun Yao Yan Zhang Cheng-Liang Wang Jing-Jiang Sun Qing-Fu Wang key laboratory of Rubber-plastics Ministry of EducationSchool of Polymer Science and EngineeringQingdao University of Science and TechnologyQingdao266042China Qingdao Research Academy of Environmental Science Qingdao266012China

L-glutamic acid(LA)is a bio-based,non-toxic,environmentally friendly material derived from *** present study reports the application of Passerini three-component polymerization(P-3CP)for the straightforward preparation of LA-based light-responsive polyesters(PLTDs)under mild *** with molar masses up to 8500 g/mol and high yields exceeding 90%are *** chemical structures and light-responsive self-immolative behavior of PLTDs are comprehensively characterized by employing ultraviolet-visible(UV-Vis)spectroscopy,size exclusion chromatography(SEC),nuclear magnetic resonance(NMR)spectroscopy,and liquid chromatography mass spectrometry(LC-MS).Meanwhile,monodisperse PLTD-based doxorubicin-loaded nanoparticles(PLTD-DOX-NP)(size=193 nm,PDI=0.018)are formulated by nanoprecipitation *** light-induced depolymerization,the PLTD-DOX-NP undergoes rapid decomposition,resulting in a burst release of 80%cargo within 13 ***,according to biological toxicity tests,the PLTD-NP possesses adequate biosafety,both before and after ***,the incorporation of P-3CP with biorenewable LA-based monomer adheres to the principles of green chemistry,significantly simplifying the synthetic pathway of light-responsive polymers.

关键词： L-glutamic acid Passerini three-component polymerization Light-responsive Polyester Nanoparticles

high-Resolution Selective Excitation of Resonance-Enhanced Multiphoton-Ionization Photoelectron spectroscopy by Shaping Femtosecond Laser Pulses

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Chinese Physics Letters 2014年第5期31卷 51-55页

作者：程文静张诗按贾天卿冯东海孙真荣 State key laboratory of precision spectroscopy and Department of Physics East China Normal University Shanghai 200062

Femtosecond laser-induced resonance-enhanced multiphoton-ionization photoelectron spectroscopy （REMPI-PS） is faced with two drawbacks of low spectral resolution and poor selective excitation due to the broad spectral bandwidth. We propose a scheme to obtain a high-resolution selective excitation of （2＋1） REMPI-PS by com- bining 7r and cosinusoidal phase modulation. Our theoretical results indicate that the （2＋1） REMPI-PS signals related to neighboring excited states can be differentiated from their indistinguishable photoelectron spectra by the 7r phase modulation, and then their selective excitation can be realized by supplementally adding the cosi- nusoidal phase modulation. Furthermore, the physical mechanism of the high-resolution selective excitation of （2＋1） REMPI-PS is explained by considering the two-photon power spectrum.

关键词： Photoelectron spectroscopy

Development of adjustable permanent magnet Zeeman slowers for optical lattice clocks

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Chinese Physics B 2017年第5期26卷 102-107页

作者：张晓航徐信业 State key laboratory of precision spectroscopy and Department of Physics East China Normal University Shanghai 200062 China

We develop a permanent-magnet Zeeman slower with adjustable magnets along the longitudinal and radial *** by four arrays of cylindrical magnets, the longitudinal magnetic field in the slower is tunable if relevant parameters vary, for example, laser detuning or intensity. The proposed Zeeman slower can be reconfigured for Sr atoms. Additionally,we demonstrate that the residual magnetic field produced by the permanent magnets in the magneto-optical trap region can be as small as 0.5 Gs.

关键词： permanent magnet slower adjustable longitudinal dipole tunable clock directions captured

Neosophoflavonoids A–C, A class of highly oxidized hybrid flavonoids from Sophora flavescens with antidiabetic effects

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Chinese Chemical Letters 2024年第10期35卷 295-298页

作者： Xu Zhang Jiang Li Kai-Zhou Lu Ya-Nan Yang Jian-Shuang Jiang Xiang Yuan Zi-Ming Feng Fei Ye Pei-Cheng Zhang State key laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia MedicaChinese Academy of Medical Sciences and PekingUnionMedical CollegeBeijing100050China

Three highly oxidized hybrid flavonoids neosophoflavonoids A–C(1,2a,and 2b)were isolated from the roots of Sophora *** A possesses a unique highly oxidized heptacyclic6/6/6/6/6/6/5 *** B and C are isomers and share the same highly oxidized hexacyclic 6/6/6/6/6/6 *** planar structures were elucidated from 1D/2D nuclear magnetic resonance(NMR),ultraviolet spectroscopy(UV),infrared spectroscopy(IR),and high resolution electrospray ionization mass spectroscopy(HRESIMS)*** absolute configurations were determined by thorough GIAO13C NMR(DP4+)calculation protocol and electronic circular dichroism(ECD)calculation *** plausible biosynthetic routes for the compounds were also *** compounds exhibited significant protein tyrosine phosphatase-1B(PTP1B)inhibitory activity with half maximal inhibitory concentration(IC_(5)0)values 3.94±0.01,0.38±0.13,and 0.70±0.01μmol/L,*** addition,compared to a positive control fenofibrate(Feno)at 20μmol/L,compounds 2a and 2b exhibited stronger inhibitory effects on lipid accumulation in the oleic acid(OA)-induced cell model at 5 and 10μmol/L.

关键词： Sophora flavescens highly oxidized hybrid flavonoids Neosophoflavonoids A-C PTP1B inhibition Lipid accumulation inhibition

New empirical formula for(γ, n) reaction cross section near GDR peak for elements with Z ≥ 60

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Chinese Physics C 2017年第4期41卷 94-107页

作者： Rajnikant Makwana S. Mukherjee 王建松陈志强 Physics Department Faulty of Science The Maharaja Sayajirao University of Baroda Vadodara-390002. India key laboratory of high precision nuclear spectroscopy and Center for nuclear Matter Science Institute of Modern Physics Chinese Academy of Science Lanzhou 730000 China

A new empirical formula has been developed that describes the（7,n nuclear reaction cross sections for isotopes with Z ≥ *** results were supported by calculations using TALYS-1.6 and EMPIRE-3.2.2 nuclear modular *** energy region for incident photon energy has been selected near the giant dipole resonance（GDR peak *** evaluated empirical data were compared with available data in the experimental data library *** data produced using TALYS-1.6 and EMPIRE-3.2.2 are in good agreement with experimental *** have tested and presented the reproducibility of the present new empirical *** observe the reproducibility of the new empirical formula near the GDR peak energy is in good agreement with the experimental data and shows a remarkable dependency on key nuclei properties：the neutron,proton and atomic number of the *** behavior of nuclei near the GDR peak energy and the dependency of the GDR peak on the isotopic nature are *** effort has been made to explain the deformation of the GDR peak in（γ,n nuclear reaction cross sections for some isotopes,which could not be reproduced with TALYS-1.6 and *** evaluated data have been presented for the isotopes ^180W,^183W,^202Pb,^203Pb,^204Pb,^205Pb,^231Pa,^232U,^237U and ^239Pu,for which there are no previous measurements.

关键词： photonuclear reactions GDR empirical formula TALYS EMPIRE cross section

On joint analysing XMM-NuSTAR spectra of active galactic nuclei

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中国科学技术大学学报 2024年第7期54卷 19-33,18,I0002页

作者： Jialai Kang Junxian Wang cas key laboratory for Research in Galaxies and Cosmology Department of AstronomyUniversity of Science and Technology of ChinaHefei 230026China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China

A recently released XMM-Newton note revealed a significant calibration issue between nuclear spectroscopic telescope array(NuSTAR)and XMM-Newton European Photon Imaging Camera(EPIC)and provided an empirical correction to the EPIC effective *** quantify the bias caused by the calibration issue in the joint analysis of XMM-NuSTAR spectra and verify the effectiveness of the correction,in this work,we perform joint-fitting of the NuSTAR and EPIC-pn spectra for a large sample of 104 observation pairs of 44 X-ray bright active galactic nuclei(AGN).The spectra were extracted after requiring perfect simultaneity between the XMM-Newton and NuSTAR exposures(merging good time intervals(GTIs)from two missions)to avoid bias due to the rapid spectral variability of the *** the correction,the EPIC-pn spectra are systematically harder than the corresponding NuSTAR spectra by■subsequently yielding significantly underestimated cutoff energy E_(cut)and the strength of reflection component R when performing *** confirm that the correction is highly effective and can commendably erase the discrepancy in best-fitΓ,E_(cut),and *** thus urge the community to apply the correction when joint-fitting XMM-NuSTAR spectra,but note that the correction is limited to 3–12 keV and therefore not applicable when the soft X-ray band data are ***,we show that as merging GTIs from two missions would cause severe loss of NuSTAR net exposure time,in many cases,joint-fitting yields no advantage compared with utilizing NuSTAR data ***,We present a technical note on filtering periods of high background flares for XMM-Newton EPIC-pn exposures in the small window(SW)mode.

关键词： active galactic nuclei X-ray spectroscopy XMM-Newton NuSTAR cross-calibration issue

Fabrication of ZnO-based thick film varistors with high potential gradient

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Rare Metals 2010年第4期29卷 390-395页

作者： KE Lei JIANG Dongmei MA Xueming State key laboratory of precision spectroscopy Department of Physics East China Normal University Shanghai 200062 China

ZnO-based thick film varistors have been fabricated by Y203 doping and low-temperature sintering, of which the sample with the best electrical properties has a high potential gradient value of 3159.4 V/mm. The effects of Y2O3 doping concentration and sintering temperature on the potential gradient of the samples were systematically investigated. The results show that the sample with the best electrical properties can be obtained by doping 0.08 mol% Y2O3 and sintering at 725℃. Under these optimum preparation conditions, the leakage current and the nonlinear coefficient are found to be 36.4 gA and 13.1. The sample with the best electrical properties has a grain size of 1.290um, a single grain boundary voltage of 4.08 V, a barrier height of 0.81 eV, and a depletion layer width of 10.2 nm, which are determined by thermionic emission. Small grain size with good grain boundary characteristics is beneficial to improve the electrical properties of varistors and promote the potential gradient.

关键词： condensed matter physics thick film varistors low-temperature sintering doping potential gradient

Dispersion Theory of Polaron in a Parabolic Quantum Dot at Finite Temperatures

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Communications in Theoretical Physics 2011年第2期55卷 345-348页

作者：孙尔林冯东海贾天卿周侃孙真荣 State key laboratory of precision spectroscopy Department of Physics East China Normal University State key laboratory of high Field Laser Physics Shanghai Institute of Optics and Fine Mechanics

By using the dispersion theory instead of the Frohlich Hamiltonian, the polaron energy in a quantum aot with a parabolic confinement potential is investigated at finite temperatures. It is found that the self-trapping energy of the polaron decreases with the increasing temperature, and the temperature effect is more obvious in quantum dots with weaker confinement.

关键词： semiconductors quantum dots electron-phonon interactions

Isotopic production cross sections of fragmentation residues produced by ^(18)O ions on a carbon target near 260 MeV/nucleon

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Chinese Physics C 2022年第11期46卷 1-6页

作者： Xiao-Dong Xu Ya-Zhou Sun Shi-Tao Wang Bo Mei Shu-Ya Jin Xue-Heng Zhang Zhi-Yu Sun Yi-Xuan Zhao Shu-Wen Tang Yu-Hong Yu Duo Yan Fang Fang Yong-Jie Zhang Shao-Bo Ma cas key laboratory of high precision nuclear spectroscopy Institute of Modern PhysicsChinese Academy of SciencesLanzhou 730000China School of nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China Sino-French Institute of nuclear Engineering and Technology Sun Yat-sen UniversityZhuhai 519082China School of nuclear Science and Technology Lanzhou UniversityLanzhou 730000China

The isotopic cross sections of residual nuclei produced in fragmentation reactions of ^(18)O projectiles impinging on a carbon target at energies near 260 MeV/nucleon were measured at the HIRFL facility in Lanzhou(China).A full identification of atomic and mass numbers of fragments was achieved from the determination of their magnetic rigidity,energy loss,and time of *** production cross sections for a dozen of nitrogen,carbon,and boron isotopes were determined with uncertainties below 30% for most of the *** obtained cross sections for N and B isotopes show a rather good agreement with previous experimental data obtained with different projectile *** cross sections for some C isotopes seem to exhibit a dependence on the projectile energy.A comparison of the data and several theoretical model calculations are presented.

关键词： heavy-ion collisions projectile fragmentation isotopic production cross sections