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Chinese Chemical Letters 2017年第4期28卷 868-874页

作者： lan-lan Li Ru-Yi Jiang Jin-xing Chen Mo-Zhen Wang Xue-Wu Ge CAS Key Laboratory of Soft Matter Chemistry Department of Polymer Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026China Petro China Company Limited Beijing 100007China

Self-healable polyacrylamide-based hydrogels were prepared at room temperature via a one-step emulsion copolymerization of acrylamide（AM）,dodecyl 2-methacryIate（DM）,and 5-acetylaminopentyl acrylate（AAPA） using sodium dodecyl sulfonate（SDS） as the emulsifier and ammonium persulfate（APS）as the *** produced linear multi-block copolymer chains are composed of randomly-linked hydrophilic polyacrylamide segments（PAM） and hydrophobic segments constituted by DM and AAPA units（P（DM-co-AAPA））.The P（DM-co-AAPA） segments will self-aggregate into hydrophobic microdomains during the polymerization process driven by the hydrophobic interactions,and finally separate from water phase,acting as the crosslinks and leading to the formation of strong hydrogels with a storage modulus as high as 400 *** hydrophobic microdomains will be dissolved in water when the temperature increases to 70℃,resulting in a temperature-responsive reversible sol-gel transition of the prepared ***,the prepared hydrogels have excellent self-healing *** broken hydrogels can be automatically healed into a body with a same strength within 2-min＇s *** work provides a new simple way to prepare reversible physical crosslinked hydrogel with high strength and self-healing efficiency.

关键词： Self-healing 5-Acetylaminopentyl acrylate Hydrogen bond Emulsion copolymerization

Exponential Convergence Rates of Markov Chains under a Weaken Minorization Condition

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Acta Mathematica Sinica,English Series 2018年第12期34卷 1829-1836页

作者： Shu lan HU Xin yu WANG School of Statistics and Mathematics Zhongnan University of Economics and Law Wuhan 430073 P. R. China School of Mathematics and Statistics Huazhong University of Science and Technology Wuhan 430074 P. R. China

In this paper, we obtain the quantitative bound of the exponential convergence rates of Markov chains under a weaken minorization condition, using the coupling method and the analytic approach. And also, we obtain the... 详细信息

关键词： Convergence rates Markov chains coupling method analytic approach

The influence of explicit tidal forcing in a climate ocean circulation model

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Acta Oceanologica Sinica 2016年第9期35卷 42-50页

作者： yu Yi LIU Hailong lan Jian Physical Oceanography Laboratory Qingdao Collaborative Innovation Center of Marine Science and TechnologyOcean University of China State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of Sciences

The eight main tidal constituents have been implemented in the global ocean general circulation model with approximate 1° horizontal *** with the observation data,the patterns of the tidal amplitudes and phases had been simulated fairly *** responses of mean circulation,temperature and salinity are further investigated in the global *** implementing the tidal forcing,wind-driven circulations are reduced,especially those in coastal *** is also found that the upper cell transport of the Atlantic meridional overturning circulation（AMOC） reduces significantly,while its deep cell transport is slightly enhanced from 9×106m3/s to 10×106 m3/*** changes of circulations are all related to the increase of a bottom friction and a vertical viscosity due to the tidal *** temperature and salinity of the model are also significantly affected by the tidal forcing through the enhanced bottom friction,mixing and the changes in mean *** largest changes occur in the coastal regions,where the water is cooled and *** the open ocean,the changes are divided into three layers：cooled and freshened on the surface and below 3 000 m,and warmed and salted in the middle in the open *** the upper two layers,the changes are mainly caused by the enhanced mixing,as warm and salty water sinks and cold and fresh water rises;whereas in the deep layer,the enhancement of the deep overturning circulation accounts for the cold and fresh changes in the deep ocean.

关键词： tidal forcing tidal mixing ocean general circulation model wind-driven circulation Atlantic meridional overturning circulation

A systematic review and meta-analysis of the Chinese literature for the treatment of achalasia

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World Journal of Gastroenterology 2008年第38期14卷 5900-5906页

作者： lan Wang You-Ming Li lan Li Chao-Hui yu Department ofGastroenterology the First Affiliated Hospital Medical CollegeZhejiang University Hangzhou 310003 Zhejiang ProvinceChina

AIM: To evaluate the effect of different approaches in the treatment of achalasia in China. METHODS: We performed a systematic review and meta-analysis of Chinese literature by searching the Chinese Biomedical Database and Chinese scientific Journals database (up to March 2008). All cohort studies (controlled or uncontrolled) in which the patients were observed for more than a year were reviewed in detail. Dichotomous outcomes were reported as relative risks (RR) with 95% confidence interval (CI) for controlled trials. The efficacy in uncontrolled trials was assessed by a pooled estimate of response rate with individual studies weighted in proportion to the sample size. RESULTS: Seven controlled trials compared the effect of botulinum toxin injection (BoTx) with pneumatic dilation (PD). PD was superior to BoTx [65.2% vs 45.3%; RR 1.47 (95% CI 1.23-1.77), P < 0.0001], and had a lower clinical relapse rate (BoTx 30.2% vs PD 10%, RR 0.32 (0.16-0.65), P = 0.001). Heller myotomy (HM) had superior remission rate compared to PD [HM 94.0% vs PD 64.1%, RR 1.48 (1.15-1.99), P = 0.002]. In uncontrolled trials, the effectiveness of PD was 86.6% (23.9%) vs 94.8% (10.6%) for HM. The main complications of PD were perforation and gastroesophageal reflux disease. CONCLUSION: HM is the most effective long-term treatment for patients with achalasia in China. In the future, controlled clinical trials on the treatment of achalasia should focus on comparing laparoscopic myotomy with or without antireflux procedure,including different partial and total fundoplication techniques.

关键词： Meta-analysis Achalasia Esophageal Treatment Pneumatic dilation Botulinum toxin injection Laparoscopic myotomy

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

A Symbol Timing Recovery Algorithm of M-PSK Signals for Burst Modem Applications with Small Packet Size

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China Communications 2016年第6期13卷 138-146页

作者： yu Chi lan Chen Chao Lv Institute of Microelectronics Chinese Academy of Sciences

Feedforward symbol timing recovery techniques are particularly important for initial acquisition in burst modems. However, these techniques either have large calculation burden or sensitive to frequency offsets. In this paper, we proposed an efficient symbol timing recovery algorithm of MPSK signals named OMQ(Ordered Maximum power using Quadratic approximation partially) algorithm which is based on the Quadratic Approximation(QA) algorithm. We used ordered statistic sorting method to reduce the computational complexity further, meanwhile maximum mean power principle was used to decrease frequency offset sensitivity. The proposed algorithm adopts estimation-down sampling structure which is suitable for small packet size transmission. The results show that, while comparing with the QA algorithm, the computational complexity is reduced by 75% at most when 8 samples per symbol are used. The proposed algorithm shows better performance in terms of the jitter variance and sensitivity to frequency offsets.

关键词： symbol timing maximum mean power ordered statistic Quadratic Approximation

On the Period Variation of the W UMa-type Contact Binary V502 Ophiuchi

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Chinese Journal of Astronomy and Astrophysics 2006年第3期6卷 331-337页

作者： Qing-Yao Liu yu-lan Yang National Astronomical Observatories/yunnan Observatory Chinese Academy of Sciences Kunming 650011

The variation in the orbital period of the W UMa type contact binary V502 Oph is analyzed. The orbital period exhibits a wavelike variation with a periodicity of 23.0 years and an amplitude of AP = 1.24 ×10^-5 days superimposed on secular decrease of dP/dt = 1.68× 10^-7 day per year. The long-term decrease may be accompanied by the contraction of the secondary at a rate of 83 m per year and a mass transfer rate from the primary to the secondary of 4.28×10^-8M· per year. The short-term oscillation may be explained by the presence of a third component. Orbital elements of the third body and its possible mass are presented.

关键词： stars: contact binary - period change - star: individual: V502 Oph

Topological Entropy of a Class of Subshifts of Finite Type

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Acta Mathematica Sinica,English Series 2018年第12期34卷 1765-1777页

作者： Jin Zhong XU lan yu WANG Key Laboratory of Space Utilization Technology and Engineering Center for Space Utilization Chinese Academy of Sciences Beijing 100094 P. R. China University of Chinese Academy of Sciences Beijing 100049 P. R. China Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 P. R. China

In this paper, we construct a special class of subshifts of finite type. By studying the spectral radius of the transfer matrix associated with the subshift of finite type, we obtain an estimation of its topological entropy. Interestingly, we find that the topological entropy of this class of subshifts of finite type converges monotonically to log（n ＋ 1）（a constant only depends on the structure of the transfer matrices） as the increasing of the order of the transfer matrices.

关键词： Symbolic dynamical system subshift of finite type topological entropy transfer matrix,Toeplitz matrix

Effect of nonlinear advection on the Indian Ocean diploe asymmetry

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Acta Oceanologica Sinica 2014年第1期33卷 77-82页

作者： WANG yu lan Jian CUI Fengjuan Key Laboratory of Physical Oceanography Ocean University of China Department of Oceanography Ocean University of China

The asymmetry of sea surface temperature anomaly（SSTA） amplitudes between the positive and negative phases of the Indian Ocean dipole（IOD） are *** dynamic effects on it are analyzed using a hybrid coordinate ocean model（HYCOM）.It suggests that the IOD is still asymmetric even when forced by a symmetric wind stress,and the asymmetry of the SSTA in the eastern pole is strong while that in the western pole is almost insignificant during the mature phase（September–November（SON））.Thus,the IOD asymmetry is primarily caused by the asymmetry in the IODE.A heat budget analysis is also conducted for the mixedlayer temperature in the eastern Indian Ocean（IODE）,which indicates that a nonlinear ocean advection cools both the positive and negative IOD ***,the nonlinear ocean advection is responsible for the asymmetry of the IOD.

关键词： asymmetry of Indian Ocean dipole dynamical effect heat budget nonlinear advection

Synthesis of Analogs of Anacardosidefrom Sem ecarpusAnacardium

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Chemical Research in Chinese Universities 1999年第3期15卷 294-299页

作者： WANG yu-lan CAI Meng-shen Institute of Chemical Metallurgy Chinese Academy of SciencesBeijing 100080P.R.China School of Pharmaceutical Sciences Beijing Medical UniversityBeijing 100083P.R.China