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β to β Terpyridylene-bridged porphyrin nanorings

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Chinese Chemical Letters 2018年第1期29卷 99-101页

作者： Bangshao Yin xu Liang Weihua Zhu ling xu Mingbo Zhou Jianxin Song Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research (Ministry of Education of China) Key Laboratory of the Assembly and Application of Organic Functional Molecules Hunan Normal University School of Chemistry and Chemical Engineering Jiangsu University

6,6＂-Terpyridylene bridged cyclic porphyrin dimer 2Ni, trimer 3Ni, tetramer 4Ni and pentamer 5Ni were obtained through Suzuki-Miyaura coupling reaction of/~,jB＇-diboryl Ni（II） porphyrin with 6,6＂-dibromo- 2,2＇：6＇,2＂-terpyridine. Free base porphyrin nanorings 2H-SH were obtained by demetallation of 2Ni-SNi with sulfuric acid in CHCI3 and then were converted into 2Zn-SZn upon treatment with Zn（OAc）2 in quantitative yields, respectively. All of these newly synthesized porphyrin nanorings were characterized by high-resolution mass spectrometry and 1H NMR spectroscopy. The photophysical properties of porphyrin nanoring were examined by UV-vis and fluorescence spectra. The electrochemical properties of 2Ni-SNi were investigated by cyclic voltammetry and differential pulse voltammetry. The UV-vis absorption spectra and fluorescence spectra of these cyclic porphyrin arrays indicate that there exist unique electronic interactions between the constituent porphyrin units in each ring. Electrochemical analysis shows that the trimer 3Ni exhibit different redox behavior, which indicate that the porphyrin units in 3Ni are presumably more coplanar than in other cyclic oorohvrin arrays.

关键词： Crossing-couplingTerpyridineNanoringPorphyrinPhotophysical properties

Development of data-driven thermal sensation prediction model using quality-controlled databases

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Building Simulation 2022年第12期15卷 2111-2125页

作者： Xiang Zhou ling xu Jingsi Zhang Lie Ma Mingzheng Zhang Maohui Luo School of Mechanical Engineering Tongji UniversityShanghai200092China Guangdong Midea Air-Conditioning Equipment Co. LTDGuangdong 528311China

Predicting the thermal sensations of building occupants is challenging,but useful for indoor environment *** this study,a data-driven thermal sensation prediction model was developed using three quality-controlled thermal comfort *** machine-learning algorithms were compared in terms of prediction accuracy and *** model was further improved by adding categorical inputs,and building submodels and general models for different contexts.A comprehensive data-driven thermal sensation prediction model was *** results indicate that the multilayer perceptron(MLP)algorithm achieves higher prediction accuracy and more rational results than the other four algorithms in this specific *** AC and NV scenarios,climate zones,and cooling and heating seasons can improve model *** submodels for specific scenarios can result in better thermal sensation vote(TSV)predictions than using general models with or without *** 11 submodels corresponding to 11 scenarios,and three general models without labels,the final TSV prediction model achieved higher prediction accuracy,with 64.7%–90.7%fewer prediction errors(reducing SSE by 3.2–4.9)than the predicted mean vote(PMV).Possible applications of the new model are *** findings of this study can help in development of simple,accurate,and rational thermal sensation prediction tools.

关键词： thermal comfort machine learning adaptive thermal comfort multilayer perceptron

Clinical and pathological portraits of axillary presentation breast cancer and effects of preoperative systemic therapy

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维普期刊数据库

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Chinese Journal of Cancer Research 2017年第4期29卷 369-373页

作者： ling xu Fang Li Yinhua Liu xuening Duan Jingming Ye Yuanjia Cheng ling Xin Breast Disease Center of Peking University First Hospital Beijing 100034China Department of General Surgery Beijing Aerospace General HospitalBeijing 100076China

There is a lack of investigation into the biological characteristics and preoperative systemic therapy （PST） for occult breast cancer （OBC）. For this study, departmental records in Breast Disease Center of Peking University First Hospital from January 2008 to December 2015 were retrospectively reviewed to identify cases of OBC. Eleven cases were included, and all patients were female, with a median age of 56 （range： 29-75） years. The sensitivity of magnetic resonance imaging （MRD was I00%, and the false positive rate was 33.3%. Based on histologic analysis of the axillary node, 9 （81.8%） cases were grade 3, and 2 （18.2%） cases were grade 2; 4 （36.4%） cases were 〉10% estrogen receptor （ER） positive and 6 （54.5%） human epidermal growth receptor 2 （HER2） positive. Nine cases （81.8%） exhibited over 30% Ki67 expression. PST was performed in 5 of the 11 cases. The lymph node response rate was 100% （5/5）, but no complete remission was achieved. In conclusion, aggressive subtypes were predominant among the included cases, and PST should be considered for OBC treatment options.

关键词： AxiUary presentation breast cancer occult breast cancer (OBC) magnetic resonance imaging (MRI) preoperative systemic therapy (PST)

Identification of a Regulatory Single Nucleotide Polymorphism in the Adiponectin (APM1) Gene Associated with Type 2 Diabetes in Han Nationality

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Biomedical and Environmental Sciences 2008年第6期21卷 454-459页

作者： MIN YANG CHANG-CHUN QIU WEI CHEN ling-ling xu MIAO YU HONG-DING XIANG Department of Endocrinolog） Peking Union Medical College Hospital Chinese Academy of Medical Sciences Beijing 100730 China National Laboratory of Medical Molecular Biology School of Basic Medicine Peking Union Medical College Institute of Basic Medical Sciences Chinese Academy of Medical Sciences Beijing 100005 China

Objective To identify the genetic defects of the the adiponectin （APM1） gene that contribute to the development of type 2 diabetes （T2DM） and determine the functional single nucleotide polymorphisms （SNPs） in the APMI gene associated with T2DM in Han nationality. Methods The APMI gene 5＇-UTR was screened by direct sequencing to identify common polymorphisms. Identified SNPs were genotyped in 585 nondiabetic controls, 278 subjects with impaired glucose intolerance （IGT） and 212 patients with T2DM. The functions of SNPs in the regulatory region were assessed by reporter gene assay. Possible association between SNPs and plasma APMI levels or metabolic parameters was statistically asses,sed. Results Three SNPs were identified in the APMI gene 5＇-UTR. A case-control study revealed that SNP -11377 G/C had significant differences in allele frequencies between T2DM patients and nondiabetic controls （G 0.314/C 0.686 vs. G 0.265/C 0.735, P=0.03）. Haplotype analysis of three SNPs in the APM1 gene showed that no significant association of haplotypes with T2DM. IGT was detected in the present study. Reporter gene assay showed that SNP did not influence the transcription efficiency in the 3T3-LI cell line. Conclusion SNP - 11377 G/C in the proximal promoter region of the APM 1 gene contributes to the development of T2DM in Han nationality but may not be a functional SNP in the APM1 gene.

关键词： Diabetes Adiponectin Single nucleotide polymorphism Reporter gene Promoter

The luminescence enhancement of Eu^(3+) ion and SnO_2 nanocrystal co-doped sol gel SiO_2 films

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Chinese Physics B 2012年第1期21卷 511-517页

作者： Zhang Xiao-Wei Lin Tao xu Jun xu ling Chen Kun-Ji National Laboratory of Solid State Microstructures School of Electronic Science and Engineering and School of PhysicsJiangsu Provincial Key Laboratory of Advanced Photonic and Electronic MaterialsNanjing UniversityNanjing 210093China

SnO2 nanocrystal and rare-earth Eu^3＋ ion co-doped SiO2 thin films are prepared by sol-gel and spin coating methods. The formation of tetragonal rutile structure SnO2 nanocrystals with a uniform distribution is confirmed by X-ray diffraction and transmission electron microscopy. Fourier transform infrared spectroscopy is used to investigate the densities of the hydroxyl groups, and it is found that the emission intensity from the 5Do-TF2 transitions of the Eu^3＋ ions is enhanced by two orders of magnitude due to energy transfer from the oxygen-vacancy-related defects of the SnO2 nanocrystals to nearby Eu^3＋ ions. The influences of the amounts of Sn and the post-annealing temperatures are systematically evaluated to further understand the mechanism of energy transfer. The luminescence intensity ratio of Eu^3＋ ions from electric dipole transition and magnetic dipole transition indicate the different probable locations of Eu^3＋ ions in the sol-gel thin film, which are further discussed based on temperature-dependent photoluminescence measurements.

关键词： sol- gel processes luminescence rare-earth ions nanostructured material

Fabrication of Anti-reflecting Si Nano-structures with Low Aspect Ratio by Nano-sphere Lithography Technique

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Nano-Micro Letters 2013年第1期5卷 18-25页

作者： Shenghua Sun Peng Lu Jun xu ling xu Kunji Chen Qimin Wang Yuhua Zuo National Laboratory of Solid State Microstructures and School of Electronic Science and Engineering Nanjing University State Key Laboratory on Integrated Optoelectronics Institute of SemiconductorsCAS

Nano-structured photon management is currently an interesting topic since it can enhance the optical absorption and reduce the surface reflection which will improve the performance of many kinds of optoelectronic devices, such as Si-based solar cells and light emitting diodes. Here, we report the fabrication of periodically nano-patterned Si structures by using polystyrene nano-sphere lithography technique. By changing the diameter of nano-spheres and the dry etching parameters, such as etching time and etching power, the morphologies of formed Si nano-structures can be well controlled as revealed by atomic force microscopy.A good broadband antireflection property has been achieved for the formed periodically nano-patterned Si structures though they have the low aspect ratio(<0.53). The reflection can be significantly reduced compared with that of flat Si substrate in a wavelength range from 400 nm to 1200 nm. The weighted mean reflection under the AM1.5 solar spectrum irradiation can be as low as 3.92% and the corresponding optical absorption is significantly improved, which indicates that the present Si periodic nano-structures can be used in Si-based thin film solar cells.

关键词： Nano-sphere lithograph Nano-patterned Si structures Antireflection

Plant Regeneration by Callus-Mediated Protocorm-Like Body Induction of Anthurium andraeanum Hort.

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Agricultural Sciences in China 2009年第5期8卷 572-577页

作者： YU Yi-xun LIU ling LIU Juan-xu WANG Jing College of Horticulture South China Agricultural University Guangzhou 510642 P.R.China

This research aims at developing a plant regeneration system from leaf and petiole explants of Anthurium andraeanum Hort., thereby establish a foundation for mass production and transformation. Using tissue culture technique, the conditions for callus induction, protocorm-like body （PLB） formation and plant regeneration from leaf explants and petiole of A. andraeanum, such as basal medium and plant growth regulator, were investigated. Totipotent callus was induced on a 1/2-strength MS medium containing 0.90 μmol L^-1 2,4-dichlorophenoxyacetic acid （2,4-D） and 8.88μmol L^-1 N6-benzyladenine （BA）. The callus exhibited complete hormone autonomy for growth and differentiation of PLBs. This callus proliferated well and was maintained by subculturing on 1/2 MS medium containing 0.90 μmol L^-1 2,4-D and 4.44 μmol L^-1 BA. On average, 8 protocorm-like bodies could be obtained from a piece of 4 mm callus after being transferred to the 1/2 MS medium with 4.44 μmol L^-1 BA after 8 wk of culture. The regenerated PLBs formed shoots and roots on 1/2 MS medium. After 24 wk of culture on these medium, well-developed plantlets for potting were produced. An efficient micropropagation method was established for indirect PLB formation and plant regeneration from leaf and petiole ofA. andraeanum.

关键词： Anthurium andraeanum callus induction plant regeneration protocorm-like body

A facile synthesis of 2-substituted-2,3-dihydro-4(1H)-quinazolinones in 2,2,2-trifluoroethanol

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Chinese Chemical Letters 2007年第6期18卷 656-658页

作者： Rong Zhang Qiao Bai ling xu Yan Hui Wang Department of Life Science and Technology Beijing University of Chemical TechnologyBeijing 100029China Institute of Materia Medica Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100050China

2-Substituted-2,3-dihydro-4(1H)-quinazolinones were obtained in high yields by condensation of anthranilamide with aryl, alkyl or heteroaryl aldehydes or ketones in the refluxing 2,2,2-trifluoroethanol without any cat... 详细信息

关键词： 2,3-Dihydro-4(1H)-quinazolinone Trifluoroethanol (TFE) Fluorinated solvent

A New Monocular Vision Measurement Method to Estimate 3D Positions of Objects on Floor

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International Journal of Automation and computing 2017年第2期14卷 159-168页

作者： ling-Yi xu Zhi-Qiang Cao Peng Zhao Chao Zhou State Key Laboratory of Management and Control for Complex Systems Institute of AutomationChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 101408China

A new visual measurement method is proposed to estimate three-dimensional （3D） position of the object on the floor based on a single camera. The camera fixed on a robot is in an inclined position with respect to the floor. A measurement model with the camera＇s extrinsic parameters such as the height and pitch angle is described. Single image of a chessboard pattern placed on the floor is enough to calibrate the camera＇s extrinsic parameters after the camera＇s intrinsic parameters are calibrated. Then the position of object on the floor can be computed with the measurement model. Furthermore, the height of object can be calculated with the paired-points in the vertical line sharing the same position on the floor. Compared to the conventional method used to estimate the positions on the plane, this method can obtain the 3D positions. The indoor experiment testifies the accuracy and validity of the proposed method.

关键词： Visual measurement, calibration, localization, position estimation monocular vision.