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Fe_(3)O_(4)@Angelica sinensis polysaccharide nanoparticles as an ultralow-toxicity contrast agent for magnetic resonance imaging

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Rare Metals 2021年第9期40卷 2486-2493页

作者： Kai Wang Xiao-Guang Xu ying-li ma Chun-Rui Sheng li-Na li li-ying Lu Jian Wang Yi-Ning Wang Yong Jiang School of materials Science and Engineering University of Science and Technology BeijingBeijing 100083China School of Instrumentation Science and Optoelectronics Engineering Beihang UniversityBeijing 100191China School of Chinese Medicine Beijing University of Chinese MedicineBeijing 100029China School of Chemistry and Biological Engineering University of Science and Technology BeijingBeijing 100083China Department of Radiology Peking Union Medical College Hospital Chinese Academy of Medical SciencesBeijing 100730China

Although iron oxide(Fe_(3)O_(4)) nanoparticles have broad application prospects as magnetic resonance imaging(MRI) contrast agent, their biocompatibility and biotoxicity still need to be improved. In this study, we prepared Fe_(3)O_(4)@Angelica sinensis polysaccharide nanoparticles(Fe_(3)O_(4)@ASP NPs) with a 9 nm Fe_(3)O_(4) core and ASP as the coating material. The Fe_(3)O_(4)@ASP NPs are superparamagnetic, can be taken up by liver and spleen macrophages in the circulatory system in vivo, and are a good-biocompatibility and low-toxicity transverse relaxation time(T_(2)) and T_(2)-star(T_(2)^(*)) magnetic resonance imaging(MRI) contrast agent for the liver. The cytotoxicity assessment using HeLa cells and the pathological tests in mice validate that Fe_(3)O_(4)@ASP NPs have low toxicity and good biocompatibility in vivo, which can be attributed to the ASP as a natural polysaccharide with good biocompatibility and its function of protecting the liver. Fe_(3)O_(4)@ASP NPs are a potential new MRI contrast agent with high signal intensity in vivo.

关键词： Superparamagnetic nanoparticles Fe_(3)O_(4) Angelica sinensis polysaccharide magnetic resonance imaging Ultralow toxicity

First Total Synthesis of 12-Hydroxy-13-methylpodocarpa-9, 11, 13-trien-3-one

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Chinese Chemical Letters 2006年第2期17卷 163-164页

作者： Cheng Lu ZHANG Xiao Lei ZHU ying Ge ma li Wei ZOU Department of Chemistry Liaoning Normal University Dalian 116029

A ftrst facile total synthesis of 12-hydroxy- 13-methylpodocarpa-9, 11, 13-trien-3-one 9 was accomplished via a strategy of AC→ABC. In the synthetic process, compound 5 was synthesized through Reimer-Teimann reaction, followed by methylation, reduction, dehydration, addition to ethylene epoxide and chlorination. The target compound 9 was finally obtained through the condensation of Grignard reagent of compound 5 with 6, followed by intramolecular cyclization, reduction and demethylation.

关键词： Total synthesis 12-hydroxy-13-methylpodocarpa-9 11 13-trien-one diterpene.

Group separation of coal components and new ideas of coal utilization as petroleum

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Mining Science and Technology 2009年第5期19卷 636-641页

作者： QIN Zhi-hong HOU Cui-li CHEN Juan ZHANG li-ying ma Jie-qiong School of Chemical Engineering and Technology China University of Mining ＆ Technology Xuzhou Jiangsu 221116 China

Four different groups of components were separated from coal under mild conditions of extraction and stripping process. Within these groups, and with pre-separation, individual utilization of all coal components can be realized, similar to petroleum components and enhance the inherent value and utilization value of coal, as well as increase environmental benefits. The characteristics of each component were analyzed with measurements by FTIR, GC/MS, TEM and the establishment of caking properties. The results show that coal can be separated into residues, ultra-pure coal, asphaltene components and light components by adding solvents for stripping into the CS2/NMP mixed extraction solution. Those four groups of components present great differences in the presence of carbon and hydrogen elements, in the structure of functional groups, in their macroscopic structure and micro-morphology and caking properties. Every component possesses its own inherent values and approaches. A new idea of coal processes and utilization, similar to the use of petroleum is proposed.

关键词： coal group components separation similarity to petroleum process and utilization

Microstructural evolution and mechanical behavior of in situ synthesized MgAl_(2)O_(4)whiskers reinforced 6061 Al alloy composite after hot extrusion and annealing

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Rare Metals 2023年第5期42卷 1732-1742页

作者： Geng Hao Chun-Sheng Shi Nai-Qin Zhao En-Zuo liu Chun-Nian He Fang He li-ying ma School of materials Science and Engineering Tianjin UniversityTianjin 300350China Tianjin Key Laboratory of Composite and Functional materials Tianjin UniversityTianjin 300350China Collaborative Innovation Centre of Chemical Science and Engineering Tianjin 300072China

In situ synthesized MgAl2O4whiskers reinforced 6061 Al alloy composites were fabricated by a powder metallurgy ***-sized MgAl2O4spinel whiskers distributed uniformly in 6061 Al alloy matrix without any interfacial product and laid along the extrusion direction after hot ***-extruded composite samples were annealed at 530,580,600 and 630℃for 1 h and examined by electron backscattered diffraction to investigate the recrystallization behavior of obtained *** and texture evolution was investigated,and it is found that the recrystallization process is inhibited by whiskers because of Zener *** fibrous grains remain until 630℃,and deformation textures still exist even in specimen annealed at 630℃.Hardness and tensile tests show that the completely recrystallized sample has an ultimate tensile strength of 218 MPa and a hardness of HV52 compared with 283 MPa and HV 69 of the unannealed *** properties of the annealed samples decline slightly with annealing temperature increasing up to 600℃.

关键词： Composite In situ synthesized whiskers Recrystallization Microstructure Texture

Electronic Structure and Properties of Cu Metal~*

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Science China mathematics 1993年第4期36卷 487-494页

作者： XIE You-Qing ZHANG Xiao-Dong ZHAO li-ying and ma Xiu-lin (Department of materials Science and Engineering, Central South University of Technology, Changsha 410083, PRC) 张晓东赵礼颖马秀林

The main purpose of the present work is to introduce a simple and effective method in order to analyse the structure and properties of both pure metals and alloys. The main points of this method are to use one-atom state instead of one-electron state and a potential function with many-atom interactions instead of Schrodinger equation. The atomic state of pure metals can be constructed by some basic atomic states which obey the Pauli exclusion principle. The electronic structure of Cu metal which is [Ar](3d_n)^(4.89)(3d_c)^(4.77)(4s_f)^(1.34) has been determined by self-conslstency method. Theoretical values of many properties of Cu metal, such as lattice constant, cohesive energy, bulk modulus and temperature dependence of thermal expansion coefficient calculated according to this electronic structure are in good agreement with experiments.

关键词： Cu electronic structrue valence bond theory potential curve elasticity thermal expansion coefficient

Scanning electron microscopic observation:three-dimensional architecture of the collagen in hepatic fibrosis rats

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Chinese Medical Journal 2007年第4期120卷 308-312页

作者： WANG Xiao-hong ZHAO Jing ZHANG Wei-guang ZHANG li-ying, ma Rui-qiong WANG li-qin ZHANG Shu-yong TIAN Long Department of Anatomy and Histoembryology Peking UniversityHealth Science Center Beijing 100083 China

Background In the process of hepatic fibrosis, the accumulation of collagen fibers is strongly related to the hepatic function. The aim of this study was to investigate the three-dimensional architecture of the collagen network in the liver of rats with hepatic fibrosis. Methods Healthy adult male Wistar rats （n=32） were randomly divided into a control group （n=16） and a hepatic fibrosis group （n=16）. In the control group, the rats were treated with peanut oil while the rats in hepatic fibrosis group were treated for 10 weeks with 60% CCI4 diluted in peanut oil. The quantity of collagen fibers was detected by Western blotting; distribution of the collagen was detected by sirius red staining and polarized microscope; the three-dimensional architecture of collagen in the liver was observed under the scanning electron microscope after fixed tissues were treated with cell-maceration using NaOH. Statistical analysis was performed using the u test. Results The quantity of collagen fibers increased significantly in the hepatic fibrosis group. With the aggravation of hepatic fibrosis, collagen fibers gradually accumulated. They interlaced the reticulation compartment and formed a round or ellipse liver tissue conglomeration like a grape framework that was disparate and wrapped up the normal liver Iobule. The deposition of collagen fibers was obvious in adjacent hepatic parenchyma, especially around the portal tracts. Conclusion Our experiment showed the collagen proliferation and displays clearly the three-dimensional architecture of collagen fibers in rat liver with hepatic fibrosis by scanning electron microscope. It can provide a morphological foundation for the mechanisms of changed haemodynamics and portal hypertension in hepatic fibrosis.

关键词： hepatic fibrosis collagen fibers scanning electron microscope three-dimensional construct

Local magnetic moment oscillation around an Anderson impurity on graphene

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 192-201页

作者： Shuai li Zhen ma Jin-Hua Gao School of Science Hebei University of Science and Technology School of Electronics and Information Zhengzhou University of Light Industry School of Physics and Wuhan National High magnetic Field Center Huazhong University of Science and Technology

We theoretically investigate the spin resolved Friedel oscillation （FO） and quasiparticle interference （QPI） in graphene induced by an Anderson *** the impurity becomes magnetic,the resulted FO becomes spin dependent,which gives rise to a local magnetic moment oscillation with an envelop decaying as r-2in real space in the doping ***,at half filling,the electron density and local magnetic moment will not oscillate but decay as *** spin resolved FO has both sublattice and spin ***,the local magnetic moment decay at half filling only occurs at one sublattice of graphene,which is quite like the phenomenon observed in the STM experiment (***ález-Herrero et al.,Science 352,437 （2016）).We further give an analytic formula about such spin dependent FO based on the stationary phase ***,we study the interference of quasiparticles around the magnetic impurity by calculating the spin dependent Fourier-transformed local density of states （FT-LDOS）.Our work gives a comprehensive understanding about the local magnetic moment oscillation around an Anderson impurity on graphene.

关键词： Friedel oscillation local magnetic moment graphene Anderson impurity

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非限域甲硫氨酸分子手性转变的第三反应通道

吉林大学学报（理学版） 2017年第5期55卷 1302-1307页

作者：祝颖熊莉马杰吉林医药学院生物医学工程学院吉林吉林132013

基于密度泛函理论中的B3LYP方法,在6-311+G(2df)基组水平上,研究非限域条件下单体甲硫氨酸分子手性转变过程的第三反应通道.通过寻找反应过程中各极值点结构,绘制完整的甲硫氨酸分子手性转变路径反应势能面,并分析各极值点的几何及电子... 详细信息

基于密度泛函理论中的B3LYP方法,在6-311+G(2df)基组水平上,研究非限域条件下单体甲硫氨酸分子手性转变过程的第三反应通道.通过寻找反应过程中各极值点结构,绘制完整的甲硫氨酸分子手性转变路径反应势能面,并分析各极值点的几何及电子结构特性.结果表明:S型甲硫氨酸分子手性C上的H原子以6C=10O原子为桥梁,转移至手性C原子的另一侧,实现了从S型到R型甲硫氨酸分子手性转变的第三反应通道;该反应路径共有4个中间体和5个过渡态,最大反应能垒为321.361 2kJ/mol,来源于第二个过渡态TS_2-S3-Met.

关键词：手性甲硫氨酸过渡态非限域

Aneuploidy in Early Miscarriage and its Related Factors

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Chinese Medical Journal 2015年第20期128卷 2772-2776页

作者： Chan-Wei Jia li Wang Yong-lian Lan Rui Song li-Yin Zhou Lan Yu Yang Yang Yu liang ying li Yan-Min ma Shu-Yu Wang Department of Reproduction Beijing Obstetrics and Gynecology Hospital Capital Medical University Beijing 100026 China

Background： Genetic factors are the main cause of early miscarriage. This study aimed to investigate aneuploidy in spontaneous abortion by fluorescence in situ hybridization （FISH） using probes for 13, 16, 18, 21, 22, X and Y chromosomes. Methods： A total of 840 chorionic samples from spontaneous abortion were collected and examined by FISH. We analyzed the incidence and type of abnormal cases and sex ratio in the samples. We also analyzed the relationship between the rate of aneuploidy and parental age, the rate of aneuploidy between recurrent abortion and sporadic abortion, the difference in incidence of aneuploidy between samples from previous artificial abortion and those from no previous induced abortion. Results： A total of 832 samples were finally analyzed. 368 （44.23%） were abnormal, in which 84.24% （310/368） were aneuploidies and 15.76% （58/368） were polyploidies. The first was trisomyl6 （121/310）, followed by trisomy 22, and X monosomy. There was no significant difference in the rate ofaneuploidy in the advanced maternal age group （≥35 years old） and young maternal age group （〈35 years old）. However, the rate oftrisomy 22 and the total rate of trisomies 21, 13, and 18 （the number oftrisomy 21 plus trisomy 13 and trisomy 18 together） showed significantly different in two groups. We found no skewed sex ratio. There was no significant difference in the rate of aneuploidy between recurrent miscarriage and sporadic abortion or between the samples fi＇om previous artificial abortion and those from no previous artificial abortion. Conclusions： Aneuploidy is a principal factor of miscarriage and total parental age is a risk factor. There is no skewed sex ratio in spontaneous abortion. There is also no difference in the rate of aneuploidy between recurrent abortion and sporadic abortion or between previous artificial abortion and no previous induced abortion.

关键词： Aneuploidy Artificial Abortion In Situ Hybridization Miscarriage Parental Age Recurrent Abortion Sex Ratio