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Properties of the high-mass star forming region IRAS 22475+5939

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Research in Astronomy and Astrophysics 2012年第7期12卷 845-856页

作者： xiao-lan Liu Jun-Jie Wang National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

IRAS 22475＋5939 has been we can still discover new characteristics well studied by previous astronomers, but about it, using the first observations of the lines from CO J=2-1, 13C0 J=2-1 and 13CO J=3-2 by the KOSMA 3m telescope. The mapping of the intensity ratio of 13CO J=3-2 and 13CO J=2-1 shows that the distribution of the temperature has two peaks, neither of which coincide with the IRAS 22475＋5939 source or the center of the HII region, but rather are located at the edge of the HII region. Overlays of the Spitzer IRAC 8 p.m with CO contours indicate that they are associated with each other and that the strongest polycyclic aro- matic hydrocarbon （PAH） emission is at the IRAS 22475＋5939 source position. The IRAS LRS spectrum at 7μm-23 μm and the PHT-s spectrum at 2μm-12μm of the IRAS 22475＋5939 source also exhibit strong PAH emission characteristics in the main PAH bands： The diversity of the PAH family should be responsible for the plateaus in the PAH emission in the PHT-s and IRAS-LRS spectra. Analysis and mod- eling in the infrared bands suggest that IRAS 22475＋5939 is more likely to be a class I young stellar object. Where this is the case, the star is likely to have a tempera- ture of Tefr-9995.8K, mass-15.34Mo, luminosity -1.54×104 L- and age 1.54-104 yr. The model shows that circumstellar disc emission is important for wavelengths between 1 and 10μm, otherwise, the envelope fluctuates for A 〉 10μm. Bipolar outflow is confirmed in the molecular cloud, and the excited star of the HII region could be the driving source of the outflow. High resolution is required fm better results.

关键词： ISM: jets and outflow -- ISM: molecular -- ISM: kinematical and dy-namics -- star formation

Notes on Piecewise-Koszul Algebras

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Acta Mathematica Sinica,English Series 2011年第5期27卷 943-952页

作者： Jia Feng LV xiao lan YU Institute of Mathematics Zhejiang Normal University Jinhua 321004 P. R. China Department of Mathematics Zhejiang University Hangzhou 310027 P. R. China

The relationships between piecewise-Koszul algebras and other ＂Koszul-type＂ algebras are discussed. The Yoneda-Ext algebra and the dual algebra of a piecewise-Koszul algebra are studied, and a sufficient condition for the dual algebra A^1 to be piecewise-Koszul is given. Finally, by studying the trivial extension algebras of the path algebras of Dynkin quivers in bipartite orientation, we give explicit constructions for piecewise-Koszul algebras with arbitrary ＂period＂ and piecewise-Koszul algebras with arbitrary ＂jump-degree＂.

关键词： Piecewise-Koszul algebras almost Koszul algebras,/C:-algebras Dynkin quivers

Intertidal area classification with generalized extreme value distribution and Markov random field in quad-polarimetric synthetic aperture radar imagery

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Frontiers of Information Technology & Electronic Engineering 2019年第2期20卷 253-264页

作者： Ting-ting JIN xiao-qiang SHE xiao-lan QIU Bin LEI Key Laboratory of Technology in Geo-spatial Information Processing and Application System Institute of ElectronicsChinese Academy of Sciences University of Chinese Academy of Sciences Huawei Software Technologies Co. Ltd.

Classification of intertidal area in synthetic aperture radar(SAR) images is an important yet challenging issue when considering the complicatedly and dramatically changing features of tidal fluctuation. The difficulty of intertidal area classification is compounded because a high proportion of this area is frequently flooded by water, making statistical modeling methods with spatial contextual information often ineffective. Because polarimetric entropy and anisotropy play significant roles in characterizing intertidal areas, in this paper we propose a novel unsupervised contextual classification algorithm. The key point of the method is to combine the generalized extreme value(GEV) statistical model of the polarization features and the Markov random field(MRF) for contextual smoothing. A goodness-of-fit test is added to determine the significance of the components of the statistical model. The final classification results are obtained by effectively combining the results of polarimetric entropy and anisotropy. Experimental results of the polarimetric data obtained by the Chinese Gaofen-3 SAR satellite demonstrate the feasibility and superiority of the proposed classification algorithm.

关键词： Intertidal classification Polarimetric synthetic aperture radar Finite mixture model Markov random field Generalized extreme value model

Adaptive fault diagnosis of sucker rod pump systems based on optimal perceptron and simulation data

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Petroleum Science 2022年第2期19卷 743-760页

作者： xiao-xiao Lv Han-Xiang Wang Zhang xin Yan-xin Liu Peng-Cheng Zhao College of Mechanical and Electrical Engineering China University of PetroleumQingdao266580China

A highly precise and timely diagnosis technology can help effectively monitor and adjust the sucker rod production system(SRPS)used in oil wells to ensure a safe and efficient *** current diagnosis method is pattern recognition of a dynamometer card(DC)based on feature extraction and *** premise of this method is that the training and target data have the same ***,the training data are collected from a field SRPS with different system parameters designed to adapt to production conditions,which may significantly affect the diagnostic *** address this issue,in this study,an improved model of the sucker rod string(SRS)is derived by adding faultparameter dimensions,with which DCs under 16 working conditions could be *** an adaptive diagnosis method is proposed by taking simulated DCs generated near the working point of the target SRPS as training ***,to further improve the accuracy of the proposed method,the DC features are improved by relative normalization and using additional features of the DC position to increase the distance between different types of *** parameters of the perceptron are optimized to promote its ***,the accuracy and real-time performance of the proposed adaptive diagnosis method are validated using field data.

关键词： Sucker rod pump Dynamometer card Adaptive fault diagnosis Sucker rod dynamics Output metering

Highly efficient one-pot,three-component synthesis of1,5-benzodiazepine derivatives

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Chinese Chemical Letters 2014年第2期25卷 327-332页

作者： xiao-Qing Li lan-Zhi Wang The College of Chemistry and Material Science Hebei Normal University

A general, mild and efficient protocol for the synthesis of ethyl 4-methyl-2-（thiophen）-2,5-dihydro-1,5- benzodiazepine-3-carboxylate is achieved for first time using H3PMo12O40 in ethanol at 0 ℃ by a one- pot, three-component condensation of various thiophene aldehydes, substituted o-phenylenediamines and ethyl acetoacetate. Compared with the conventional synthesis method, this procedure has the advantages of convenient operation, excellent yields, and environmentally benign. A plausible formation mechanism has been proposed. The structure of the products is characterized by1H NMR, IR, MS and elemental analysis.

关键词： One-pot Synthesis 1,5-Benzodiazepine derivative

β-CuGaO_(2):a ferroelectric semiconductor with narrow band gap as degradation catalyst for wastewater environmental remediation

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Rare Metals 2022年第3期41卷 972-981页

作者： Ming-Cai Yao xiao-Jie Wu lan-lan Xu Fan-Zhi Meng Qiang Yang Jian Meng xiao-Juan Liu State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China College of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China School of Materials Science and Engineering Changchun University of Science and TechnologyChangchun 130022China

As a narrow band gap semiconductor,wurtziteβ-CuGaO_(2)has drawn increasing attention in the area of solar ***β-CuGaO_(2)has been theoretically predicted to possess ferroelectric polarization,its experi-mental ferroelectric characterization and practical appli-cations have not yet been ***,firstly we experimentally confirmed its ferroelectric property via hysteresis loop *** result showed a rema-nent polarization value of 10.20μC·cm^(-2) with low coer-cive electricfield of 6.45 kV·cm^(-1) at 20 Hz at room temperature,while the leakage current density(J)value was found to be 1.188 A·cm^(-2),which suggested the property of a larger remnant polarization with low coercive electricfield than current value if the compactness was ***,the synergistic effect of ferroelectric and semiconductor was comparatively highlighted by the experiment of pollutant *** 30 min,methyl orange degradation efficiency had reached 30.73%only in the case of spontaneous polarization(electricity),while it could reach 67.58%under the effect of pre-po-larizedβ-CuGaO_(2)powder due to the modulating orienta-tion of ferroelectric *** irradiated(light),it was up to 92%within 30 min;in comparison,it merely took 16 min up to 92%degradation efﬁciency under both illu-mination and *** without illumination,it was 92.01%with 30 min in the condition of ordinary ultrasonic vibration(force)while under both illumination and ultrasonic vibration,only 11 min was spent to reach 92.79%degradation efﬁ*** these results felici-tously indicated thatβ-CuGaO_(2)had fascinating potential in energy harvesting(such as electricity,light,force)and transformation as wastewater environment remediation catalyst.

关键词： β-CuGaO_(2) Ferroelectricity Narrow band gap Large remanent polarization Degradation catalysts

Some additive results on Drazin inverse

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Applied Mathematics(A Journal of Chinese Universities) 2015年第4期30卷 479-490页

作者： LIU xiao-ji QIN xiao-lan Julio Benítez Faculty of Science Guangxi University for Nationalities Universidad Politécnica de Valencia Instituto de Matemática Multidisciplinar

In this paper, we investigate additive results of the Drazin inverse of elements in a ring R. Under the condition ab = ha, we show that a ＋ b is Drazin invertible if and only if aaD （a ＋ b） is Drazin invertible, where the superscript D means the Drazin inverse. Furthermore we find an expression of （a ＋ b）D. As an application we give some new representations for the Drazin inverse of a 2 × 2 block matrix.

关键词： Drazin inverse ring block matrix.

Zwitterionic hyaluronic acid derivatives for co-delivery of both chemotherapeutic and nucleic acid drugs in breast cancer treatment

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Nano Research 2025年第1期18卷 607-617页

作者： Ruo-Lin Jiang Hui-Na Liu Yu-Fan Yang Zhi-Cheng Zhang Qi Dai xiao-Yan Bao Lin-Jie Wu Ya-xin Qin xin Tan xiao-Yan Sun Xu-Fang Ying Zhi-Qing Ben Min Han Institute of Pharmaceutics College of Pharmaceutical SciencesZhejiang UniversityHangzhou 310058China Department of Radiation Oncology Key Laboratory of Cancer Prevention and InterventionThe Second Affiliated HospitalCollege of MedicineZhejiang UniversityHangzhou 310058China Hangzhou Institute of Innovative Medicine Zhejiang UniversityHangzhou 310058China Jinhua Institute of Zhejiang University Jinhua 321299China National Key Laboratory of Advanced Drug Delivery and Release Systems Zhejiang UniversityHangzhou 310058China Polytechnic institute Zhejiang UniversityHangzhou 310015China

Traditionally,hyaluronic acid has been widely used for drug delivery,but the current application bottleneck is that hyaluronic acid is hydrophilic and electronegative,which makes it difficult to carry hydrophobic drugs and small interfering RNA(siRNA)with the same *** on previous studies,we designed and synthesized hyaluronic acid nanocarriers HA-spermine/N,N,N-trimethylcystamine/DOX-TPP(HSTD)for loading siRNA to overcome the problem of siRNA release caused by strong electrostatic ***,N,N,Ntrimethylcystamine in the carrier can be degraded by intracellular glutathione to completely and rapidly release siRNA,thus promoting ***,when codelivered with the chemotherapy drug doxorubicin(DOX),this novel nanocarrier showed promising synergy in inhibiting tumor growth.

关键词： zwitterionic hyaluronic acid N N N-trimethylcystamine small interfering RNA(siRNA) doxorubicin

INDUCED SUBGRAPH IN RANDOM REGULAR GRAPH

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Journal of Systems Science & Complexity 2008年第4期21卷 645-650页

作者： lan xiao Guiying YAN Yuwen WU Wei REN Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China.

Let Gn,d be a random d-regular graph with n vertices, where d = o（n）. Given a fixed graph H, YH denotes the number of induced copies of H in Gn d In this paper, the authors determine the threshold of the event ＂YH ... 详细信息

关键词： Induced subgraph Poisson distribution random regular graph strictly balanced threshold.