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Chinese Journal of Structural Chemistry 2019年第3期38卷 351-361页

作者： zhang zhan-rui FENG Guo-Qiang School of Physics Huazhong University of Science and Technology Department of Mechanical and Aerospace Engineering North Carolina State University Department of Physics and Mechanical & Electrical Engineering Hubei University of Education

Three unique metal-organic framework coordination polymers, [Eu_2(bptc)(bdc)_2(H_2O)]_n(1), [Gd_2(bptc)(bdc)_2(H_2O)_4]_n(2) and [Dy_2(bptc)(bdc)_2(H_2O)_4]n(3)(1,2-H_2 BDC = 1,2-benzenedicarboylic acid, H_2 bptc = 4,4?-biphenyldicarboxylic acid) were synthesized by mixing two different multi-carboxylic acids with Ln2 O3(Ln = Eu, Gd and Dy) in hydrothermal condition. The three compounds are all three-dimensional and compounds 2 and 3 contain 4.289 × 6.507 ?~2 rectangularshaped one-dimensional open channels along the a direction. Additionally, the magnetic, luminescent and thermogravimetric properties were studied in detail.

关键词： metal-organic framework mixed carboxylates rare earth metals physical properties

Polarity-activated super-resolution imaging probe for the formation and morphology of amyloid fibrils

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Nano Research 2020年第9期13卷 2556-2563页

作者： Zheng Lv Li Li Zhongwei Man Zhenzhen Xu Hongtu Cui rui zhan Qihua He Lemin Zheng Hongbing Fu Beijing Key Laboratory for Optical Materials and Photonic Devices Capital Normal UniversityBeijing 100048China Tianjin Key L aboratory of Molecular Optoelectronic Sciences Institute of Molecular PlusTianjin UniversityTianjin 300072China 3 The Institute of Cardiovascular Sciences and Institute of Systems BiomedicineSchool of Basic Medical SciencesKey Laboratory of Molecular Cardiovascular Sciences of Ministry of Education NHC Key Laboratory of Cardiovascular Molecular Biology and Regulatory PeptidesHealth Science CenterPeking UniversityBeijing 100191China China National Clinical Research Center for Neurological Diseases Tiantan HospitalAdvanced Innovation Center for Human Brain ProtectionThe Capital Medical UniversityBeijing 100050China

The formation of amyloid plaques usually occurs in the early-stage of Alzheimer’s disease(AD).Stimulated emission depletion(STED)imaging provided a powerful tool for visualizing amyloid structures on the nanometer ***,many commercial probes adopted in detecting amyloid fibrils are inapplicable to STED imaging,owing to their unmatched absorption and emission wavelengths,small Stokes'shift,easy photo-bleaching,***,we demonstrated a polarity-activated STED probe based on an intramolecular charge transfer donor(D)-7c-acceptor(A)*** electron-rich carbazole group and the electron-poor pyridinium bromide group,linked by 7i-conjugated thiophen-bridge,ensure strong near infrared(NIR)emission with a Stokes'shift larger than 200 *** tiny change in polarity before and after binding with amyloid plaques leads to a transition from weakly emission charge-transfer(CT)state(Φ<0.04)to highly emissive locally-excited(LE)state(Φ=0.57),giving rise to a fluorescence Turn-On *** with large Stokes'shift,good photostability and high depletion efficiency,the super-resolution imaging of the formation and morphology of amyloid fibrils in vitro based on this probe was realized with a lateral spatial resolution better than 33 nm at an extremely low depletion ***,the ex-vivo super-resolution imaging of(E)-1-butyl-4(2-(5-(9-ethyl-9Hcarbazol-3-yl)thiophen-2-yl)vinyl)pyridinium bromide(CTPB)probe in Aβ plaques in the brain slices of a Tg mouse was *** research provides a demonstration of the super resolution imaging probe of amyloid fibrils based on polarity-response mechanism,providing a new approach to the development of future amyloid probes.

关键词： polarity-activated amyloid fibrils super-resolution imaging charge transfer near infrared(NIR)emission

INFLUENCE OF CAPILLARITY ON NANO-LITER FLOWRATE MEASUREMET WITH DISPLACEMET METHOD

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Journal of Hydrodynamics 2007年第5期19卷 594-600页

作者： GUO Qiang CHENG rui SILBER-LI zhan-hua State Key Laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China Shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 China

Nanoqiter flowrate measurements in micro-tubes with displacement method were performed and the effect of capillarity force on the accuracy was investigated through lab experiments and theoretical analysis in this article. The experiments were conducted under the pressure drops ranging from 1 kPa to 10 kPa in a circular pipe with a diameter of 50 pm, to give the pressure-flowrate （P-Q） relation and verify the applicability of the classical Hagen-Poiseuille （HP） formula. The experimental results showed that there existed a discrepancy between the experimental data and the theoretical values predicted by the HP formula if the capillary effect was not considered, which exceeded obviously the limit of the system error. And hence a modified formula for the relation, taking the capillary effect into account, was presented through theoretical deduction, and after the HP formula had been modified the error was proved to be less than 3%, which was permitted in comparison with the system error. It was also concluded that only by eliminating the effect of the capillary force in experiments could the original HP formula be employed to predict the pressure-flowrate relation in the Hagen-Poiseuille flow in the micro-tube.

关键词： nano-liter flowrate measurement,Hagen-Poiseuille (HP) formula displacement method,capillarity force

α-C(sp^(3))-H Arylation of Cyclic Carbonyl Compounds

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Natural Products and Bioprospecting 2021年第4期11卷 379-404页

作者： Mei Wang Wei Wang Dashan Li Wen-Jing Wang rui zhan Li-Dong Shao Yunnan Key Laboratory of Southern Medicinal Utilization School of Chinese Materia MedicaYunnan University of Chinese MedicineKunming 650050China School of Chemistry and Chemical Engineering Yunnan Normal UniversityKunming 650050China

α-C(sp^(3))-H arylation is an important type of C-H *** biologically significant natural products,chemi-cal intermediates,and drugs have been effectively prepared via C-H *** carbonyl compounds comprise of cyclic ketones,enones,lactones,and ***α-C(sp^(3))-H arylation of these compounds have been exhibited high efficiency in forming C(sp^(3))-C(sp^(2))bonds,played a crucial role in organic synthesis,and attracted majority of interests from organic and medicinal *** review focused on the most significant advances including methods,mechanism,and applications in total synthesis of natural products in the field ofα-C(sp^(3))-H arylations of cyclic carbonyl compounds in recent years.

关键词： C-H functionalization α-C(sp^(3))-H arylation Cyclic carbonyl compounds

6,7-seco-ent-Kaurane diterpenoids from Isodon sculponeatus and their bioactivity

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Chinese Chemical Letters 2014年第4期25卷 541-544页

作者： Hua-Yi Jiang Wei-Guang Wang Min Zhou Hai-Yan Wu rui zhan Xue Du Jian-Xin Pu Han-Dong Sun State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of Sciences University of Chinese Academy of Sciences

One new 6,7-seco-ent-kaurane diterpenoid, sculponin T （1）, was isolated from the aerial parts of lsodon sculponeatus, along with four known analogs, sculponeatin J （2）, sculponeatin K （3）, sculponeatin C （4）, and sculponeatin Q （5）. Their structures were elucidated by extensive spectroscopic analysis and by comparison with data reported in the literature. Significant cytotoxic activity was observed for compound 2 against five human tumor cell lines with IC50 values ranging from 1.8 μmol/L to 3.3 μmol/L, and it also inhibited NO production in LPS-stimulated RAW264.7 cells, with IC50 value of 3.3 μmol/L.

关键词： lsodon sculponeatus 6 7-seco-ent-Kaurane diterpenoid Cytotoxicity Anti-inflammatory activity

稀土改性纳米固体超酸SO_4^(2-)/ZrO_2-CeO_2-SiO_2催化剂的研究

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稀土 2009年第3期30卷 84-88页

作者：战瑞瑞北华大学化学与生物学院吉林吉林132013

采用稀土改性及低温陈化技术合成了新型的纳米固体超酸催化剂SO42-/ZrO2-CeO2-SiO2,用XRD、XPS、TEM、FT-IR、DTG/TG等手段对催化剂进行表征,结果表明,酯化催化活性及稳定性均有大幅度提高。最佳制备条件:陈化温度-15℃,焙烧温度为500℃... 详细信息

采用稀土改性及低温陈化技术合成了新型的纳米固体超酸催化剂SO42-/ZrO2-CeO2-SiO2,用XRD、XPS、TEM、FT-IR、DTG/TG等手段对催化剂进行表征,结果表明,酯化催化活性及稳定性均有大幅度提高。最佳制备条件:陈化温度-15℃,焙烧温度为500℃,焙烧时间为3h。

关键词：纳米固体超酸催化酯化稀土

REAL-TIME MEASUREMENT QUALITY EVALUATION FOR PASSIVE AND WIRELESS RESONANT SAW SENSOR

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REAL-TIME MEASUREMENT QUALITY EVALUATION FOR PASSIVE AND WIR...

2015全国压电和声波理论及器件技术研讨会

作者： Bo-quan LIU Chen-rui zhan Shanghai Jiao Tong University

The passive wireless surface acoustic wave（SAW）sensors are advantageous for the applications under harsh environmental *** wireless transmission poses great challenges in the measurement quality due to the passive SAW sensors have no signal processing *** paper proposes a method to predict the measurement *** proposed approach is evaluated in simulations and practical *** measurement quality prediction results are identical to the practical standard deviation.

关键词： Resonant SAW sensor Passive wireless Real-time measurement quality SNR

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美国公立高校董事会的法律地位述评

比较教育研究 2006年第10期27卷 57-62页

作者：王绽蕊北京航空航天大学高等教育研究所北京100083

董事会是美国高校的法定代表机关。按照美国公立高校或高校系统董事会的法律地位,可以将它们分为具有宪法权力的公立高校或高校系统董事会与具有普通法规权力的公立高校或高校系统董事会两种类型,前者享有较大的自治权,后者则受到较多... 详细信息

董事会是美国高校的法定代表机关。按照美国公立高校或高校系统董事会的法律地位,可以将它们分为具有宪法权力的公立高校或高校系统董事会与具有普通法规权力的公立高校或高校系统董事会两种类型,前者享有较大的自治权,后者则受到较多的法律法规和立法机关等公共制度组织的规制。通常情况下,由宪法对公立高校或高校系统董事会进行规制比由普通法规进行规制具有更大的效率优势。

关键词：公立高校董事会法律地位宪法权力普通法规权力美国法定代表机关

Two Natural ent-kauranoids as Novel Wnt Signaling Inhibitors

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Natural Products and Bioprospecting 2014年第3期4卷 135-140页

作者： Jing zhang Ling-Mei Kong rui zhan Zhen-Nan Ye Jian-Xin Pu Han-Dong Sun Yan Li State Key Laboratory of Phytochemistry and Plant resources in West China Kunming Institute of BotanyChinese Academy of ScienceKunming 650201YunnanChina University of Chinese Academy of Science Beijing 100049China

Constitutively active Wnt signaling frequently occurs in most colon ***,inhibitors of Wnt signaling pathway could provide rational therapeutic effects for colorectal *** this paper,we identified two inhibitors of Wnt signaling pathway,rabdoternin B and maoecrystal I from a natural ent-kauranoid library by a dualluciferase reporter gene *** two compounds inhibited Wnt signaling pathway in a concentration-dependent manner and exhibited selective cytotoxicity toward a number of colon carcinoma cell lines SW480,HCT116,and HT29,with only weak cytotoxicity towards the normal colonic epithelial cell line *** B and maoecrystal I treatment induced G2/M phase arrest efficiently in SW480 cells as revealed by flow cytometry analysis.A further study found that maoecrystal I decreased the expression of Wnt signaling target genes,including c-myc,cyclin D1,survivin and Axin2 in colon cancer *** our data suggests that rabdoternin B and maoecrystal I are novel inhibitors of canonical Wnt signaling pathway and may possess potentials for colon cancer therapy.

关键词： Natural ent-kauranoids Wnt signaling Inhibitors Colon cancer

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辣椒摄入与胃癌发病风险关系的Meta分析

中国循证医学杂志 2019年第9期19卷 1030-1036页

作者：詹锐汤绍辉暨南大学附属第一医院消化内科

目的系统评价辣椒摄入与胃癌发病风险的关系。方法计算机检索PubMed、EMbase、Web of Science、The Cochrane Library、WanFang Data、VIP和CNKI数据库,搜集辣椒摄入与胃癌发病风险关系的流行病学研究,检索时限均从建库至2017年4月。由... 详细信息

目的系统评价辣椒摄入与胃癌发病风险的关系。方法计算机检索PubMed、EMbase、Web of Science、The Cochrane Library、WanFang Data、VIP和CNKI数据库,搜集辣椒摄入与胃癌发病风险关系的流行病学研究,检索时限均从建库至2017年4月。由2位评价员独立筛选文献、提取资料并评价纳入研究的偏倚风险后,采用Stata 12.0统计软件进行Meta分析。结果共纳入18个研究,包括17个病例-对照研究和1个队列研究,共计13142例受试者。将纳入研究分为定量组和非定量组,Meta分析结果显示:①在定量组,中至大量食用辣椒为胃癌危险因素[OR=1.55,95%CI(1.13,2.14),P=0.008],少量食用辣椒与胃癌的发生无明显相关性[OR=0.63,95%CI(0.26,1.50),P=0.297];②在非定量组,显示食用辣椒为胃癌的危险因素[OR=1.37,95%CI(1.09,1.74),P=0.008];③亚组分析结果显示:亚洲人群中至大量食用辣椒与胃癌的发生显著相关[OR=2.24,95%CI(1.88,2.67),P=0.005],但少量食用辣椒则与胃癌的发生不相关[OR=0.62,95%CI(0.33,1.18),P=0.144]。结论辣椒摄入与胃癌发生的关系尚不明确,但中至大量食用辣椒可能与胃癌的发病风险相关,特别是在亚洲人群中。

关键词：辣椒胃癌相关性系统评价 Meta分析